Recently, I Made A Handmade Birthday Card For My Boyfriend

Recently, I made a handmade birthday card for my boyfriend and I sprayed the decorations with a black spray paint and stuck them on the card. I bought lunch for him and we were in a hurry so I placed the card in the paper bag With the food (which is placed in a plastic container). He left it unopened for 30 minutes and finally ate the food I bought him. 10 hours later, he complained that he is having a stomach ache and now I'm worried that it might be due to the odor from the paint? Maybe I'm just paranoid because he didn't eat the whole day except the food I gave him. Doctor, I need your advice, please help