Saw flashes of light like a strobe when I closed my eyes, what does this mean?could it be related to my panic attacks..?
It could be the beginnings of a migraine. There are things called prodromes tht occur which show up as weird flashes, spots, patterning, and other anomalies which mess with your central vision right before a migraine. Second possibility, ocular migraines (http://www.webmd.com/migraines-headaches/ocular-migraine-basics#1. So it may have absolutely nothing to do with panic attacks at all. See your doctor if this happens again for an evaluation.
UFO alien demons.