You absolutely risked pregnancy by having unprotected sex 3 times. Are you trying to get pregnant? That's a good way to make that happen. You'll need to take a pregnancy test now. If you are not pregnant this time, buy some condoms or get on birth control to prevent pregnancy. good luck
Light cramping can be a sign of pregnancy and sometimes precum can get you pregnant even though its unlikely. I would test ASAP
and no, I don't believe he came in me