There is a wasp in my room under my sweater - what should I do? I think it's angry!?

2 days ago I found a wasp in my room. I tried to get it to fly out of my window but instead it flew into my sleeve. I immediately took off the sweater as fast as I could and it did not sting me (the sleeve is pretty wide). I dropped the sweater on the floor and couldn't find the wasp. 5 minutes later I forgot everything about it. 10 minutes ago though I lifted up the sweater a little bit and I could hear it. After 2 days without food I would think it's pretty aggressive. I am pretty afraid of wasps - I don't know if it is still under my sweater. It is night but I have the light in my room turned on - is it safe to try to kill it? And how should I do it?