Is it safe for him tanyone to ejaculate into your body? No way. Have you and your partner both been tested for sexually transmitted disease and infection at least twice, and have you been ONLY with each other -- in addition to the testing -- for six months or more, and did you always practice safer sex with other partners before that? If so, it's relatively safe. If not, it's nothing close to safe.
As far as pregnancy goes, the pill by itself -- WHEN TAKEN CORRECTLY -- is about 98% effective. But since pregnancy doesn't endanger your health the way disease and infection does (and it's curable), we advice using condoms, even if you're on the pill. Anyone thinking in your best interest would.
As far as orgasm, what we -- and most sex therapists -- would tell anyone who has yet to orgasm, the solution starts in your own two hands. Masturbate. Once you find the things that feel best to you, and that may bring you to orgasm, then you're equiippped to work on them with a partner.
But as we've said again and again, sex isn't about orgasm. Sex is about intimacy, about pleasure, and about enjoying your body, which you can do regardless. No one position or technique works for everyone, except for this: learn how your body responds to touch and to your own sexuality, and communicate that to your partner.