Orgasm😩

I seriously cannot orgasm ever! My past boyfriend was the only one that has gotten me to orgasm during sex. I've only been able to orgasm whenever I was on top of him. My new SO is very very skinny and I'm a little larger than him and feel like if I get on top, I will hurt him :( we've tried once but I got to worried and couldn't relax! I mean the sex is still awesome but I just never get to orgasm:/ should I just say fuck it and get on top or just keep going like we are? He's even tried fingering me and oral but nothing can get me even close. I just wish it was easier 😞