Too Nervous to Orgasm

So I’ve only been with three people sexual on person I was with for 6 years then he passed away. I wasn’t with anyone for two years. Then I finally decided to date this other guy it didn’t work out. Now I have a fwb (the 3rd person) a year later after the last guy. And for some reason with my fwb I find myself really nervous. Like I wanted to spicy it up. I wanted to mast**bate (idk if we can use words like this on here) while he watched me and stroked himself. But I started to cover my face not sure why. Even when he’s on top I sometimes cover my face. Which I’ve never done before. And I also feel myself getting close to an orgasm but I never can with him. I just always feel close. Even when I “flick the bean” with him watching I can’t get myself off. Or with a vibrator I can’t if he’s there. But when I’m alone I can. And I’m not sure how to shake this thing I have going on. I feel extremely comfortable around him. But I’ve never been intimate with someone that I wasn’t dating. So idk if that is why but I would love advice because I’ve never had this problem before but I keep finding myself getting in my head for no reason.