can’t reach the big o...

I’ve been sexually active for a year now (always using protection !) but after 3 different partners i can’t seem to reach the big o...i get close with my current partner but i can never actually do it - either he changes pace or i get scared since i’ve never actually orgasmed before. i just bought a vibrator and i haven’t had any luck with that so far either..dunno what to do :/