No orgasm

It was my boyfriends first time eaten a girl out, me. I've been eaten out before and never orgasmed and he couldn't get me to either. It was frustrating cuz I want to please him. Like I would get this amazing feeling like in my lower stomach/uterus area but it would go away fast. It felt amazing and I loved it. He would finger me and eat me out going back and forth and I feel like I'd get close but nothing happens. What do I need to do? Or what does he need to do? What does it feel like so I know and to tell him to keep going? How do I make myself orgasm?