giving my boyfriend nude pics of me

I've been dating my boyfriend for over a year and I really trust him. He been asking for a while if he could have a nude pic of me to have in his phone for his alone time. I always said no cuz I once did this when I was 15 and I got blackmailed and it scared me. Whenever I have sent him stuff it's been through Snapchat but today I let him take a picture of me naked from neck down and he said he has it locked away in his phone where no one can see it. He said he swears he would never show anyone cuz according to him "why would I want to show someone what's mine" 😂 I really trust him of course and he said he never do anything wit them if we broke up and I trust him totally. I guess I'm just paranoid about my last experience. Do u think it's ok I let him have one without my face ??? And do u let ur boyfriends/hubby keep pics of you ???