Odd pattern of light on my ceiling

This night I had a strange dream. It started with there being a very large red ant on the student's flat I live in. In the waking world one of our cats caught a mouse just before I went to bed, and this ant was about as big as a mouse and roughly had the same curving as the dead mouse, so I think the ant and mouse were linked. Anyway, in the dreamworld me and some flatmates that were apparently in the kitchen too, decided this ant had to be caught. At first we caught it in a bag and sealed it airtight. Then suddenly however some flatmates left and the remaining two (me and someone else) suddenly decided the ant now had to be put in some sort of small can. I then shook the can to kill the ant. Suddenly it was my flatmate not me who was shaking the ant. He tought it was dead, I was still not sure, and when he wanted to look, the ant escaped.

We then pursued it through the kitchen and he stepped on it, which became very bloody (red blood, which I believe ants don't have), but the ant was still not dead. Strong force (not clear what exactly it was) was used against the ant again a few times (by then it was on the couch, it didn't climb up there though, it just was there suddenly). The strong force severed several large body parts, but the front part and back part were still moving and trying to get to eachother. This was when the ant started kind of morphing into our other cat (the one that did not catch the mouse), and we did not try to kill it anymore. The body parts of the ant still remained on the couch though and the cat was jumping around on the couch (in a non-cat manner, more like a mad cow manner).

This was about when I woke up and I saw strange patterns of light on my ceiling. I am quite certain this part was no dream anymore. Directly after, I checked digital clocks and entered a log into my computer, the log was still there when I woke up again hours later. The lights looked at how a lasershow could look when projected into your room, but the nearness to my window and the way my luxaflex is aligned and the fact that a board of wood covers the upper part of the window, would make that impossible. The lights danced around a bit like would sunlight reflected by a pool of water. They were aligned somewhat in a grid-fashion and were thin green lines (a soft kind of green). Sometimes it also looked a bit like a board of electronics would look with its copper tracks. I looked at it for perhaps 5 seconds (probably seemed like 30, hard to guess at such times) and was considering getting my glasses. The lines of light seemed strangely sharp, and considering that without my glasses I cannot see sharp beyond 10 centimeters, this is odd. Once I had my glasses on however, the lights started to fade. It was actually only then, not earlier, that I recognised somewhat of an electronics-patten in it, instead of just a grid of perpendicular thin green lines. Not long after the pattern was gone entirely. I looked around at other places in my room if it went there, but the room was normal now. I also tried to look outside to see if someone was playing with a laserpointer or projector, but then realised it could never have reached my ceiling through my luxaflex.

I then got out of bed, tried to find my pencil but realised I had let it along with my other D&D stuff in the living room. I then somewhat reluctantly decided to use one of my computers (which are on at night), fearing however that it could magically crash this night making my text disappear, leaving me to wonder wether the lights were a dream too. It did not crash however. In this log I recorded a time of 6:34 CEST (4:34 UTC) that this happened. I got out of bed a few times to add more parts to the log, until about 6:44. The last-modified time of the file matches the time I remembered and wrote down. When I went to bed again, I later came near to a lucid dream (I realised I was dreaming, then was afraid I would wake up soon and then believed that I was still in my pre-sleep slumber mode and was not really dreaming, so I did not try to become lucid). Maybe I was in my pre-sleep slumber, or maybe it only seemed like that.

I did do something different before going to bed though, and this was thinking strongly of a Norse rune and deity (Berkano and Idunna). Someone has recently introduced me to these subjects and I am looking into it a bit. It could be somehow related to the lights I saw. Considering that the lights seemed sharp without my glasses, it could be a physical and visual artifact too, but I don't fully believe it was just an error in my eyeball or neurons.

I did think about the fact that reality is an illusion, and that the grid I saw could be a temporary hole in the illusion (revealing a computer-ish system behind the illusion). I now realise I should have jumped up and put my hand on the grid, but somehow you don't realise these things 5 seconds after waking up. Anyway, has anyone ever experienced something similar? Could the lights have been related to the rune and deity I thought about before sleeping, is it abduction-related, was it a hole in the illusion, or something else?