Boyfriend ejaculated on my chest. i wiped it off and took a shower right after. some of the water went inside of me. could i become pregnant?

Not that way: That alone won't create a pregnancy, but the same opportunities for a boyfriend to ejaculate on one's chest will sooner or later lead to ejaculations elsewhere, and lead to pregnancy unless good contraceptive use is started about now.

Unlikely: but you need counseling , various available contraceptive measures , have to see your doctor and plan your future