I can’t orgasm ,help please.

So I’ve been masturbating for awhile and I’ve NEVER orgasmed like when I use my vibrator I hold it on my clit but I start shaking and the feeling is just to much and I stop but other times I feel this pressure in my lower stomach building then it just stops like nothing happens and when my boyfriend penetrates me and plays with me it feels good but I never cum and I always feel so unsatisfied in the end, do y’all know how to help with this or have any tips or suggestions?