Can't Orgasm during sex

I started messing around with someone and I cannot get myself to orgasm. I've always had difficulty orgasming and this hasn't been the first time.

I'm on Adderall and its my first time topping someone but I really want to be able to cum for them. I know its partly nervousness and partly the medication.

However, I can masturbate and orgasm just fine when i'm alone, even on the meds but for some reason, even having abstained from masturbating for a week does not allow me to cum from anal sex. I don't know if its because i'm circumcised and theres less sensitivity or due to the way anal sex feels, its just stimulating me enough or what

Has anyone got any good tips? Or experiences of their own?