Playing CSGO 4:3 Stretched eye distortion?

I've recently changed my rez to 4:3 stretched and its helped me hit more targets and overall made me alot better right after switching but i played like a 6-7 hour session and when i was done and went off my pc, everything i look at looks distorted and wider than before, like even right now looking at my keyboard it looks really wide, and when i walk behind a car for example, the back of the car looks almost comically wide. is this damaging my eyes? is there any studies online showing the effects on the eyes of playing stretched rez?