I breathed in a lot of bad chemicals?

I was at my friends house, and he was in the room painting with acrylic, or something. It wasn't spray paint, I told him to put it away because it smelled really bad, and we had no ventilation, but he refused to do so. I believe it was because he only got an hour of sleep the night before, and he wasn't thinking clearly. So I was sitting there playing video games, with that smell in the air. Because I was occupied with something I forgot about what he was doing, and we both had massive headaches after a few hours went by, and then his mom came in and told us to open some windows because she could smell it downstairs. I took some melatonin after. So, my question would be, what are the consequences of this happening? I think that stuff kills brain cells or something. So is that what happened to me? I did have a rather large headache. I worry about basically everything, so I couldn't even sleep last night because I was wondering if there were any side effects happening to me. Someone please help!