how do i tell my boyfriend that sex makes me uncomfortable??

so im 16 and my boyfriend and i have been together for about 3 months. weve had sex and done other stuff before, but ive come to realize that the majority of sexual stuff just makes me way uncomfy. like i dont wanna touch a dick man. i dont want it in my hand, in my mouth, anything like that. im kinda fine with actual intercourse i guess?? but i just dont like other stuff. like if he touches me i get really insecure and i kinda playfully tell him to stop because i dont want him to think that i dont want him, because i do, but im also just really insecure and uncomfortable with anything regarding sex in general i guess?? idk how to tell him this tho please help. if this helps it makes any more sense, i have anxiety and im nonconfrontational so talking about things is not my strong suit.