So me and my boyfriend had sex the end of dec and then i start my period like 4 days later then now i've been wait for my period could i be pregnant ?

Possible?: If you have had unprotected sex, you can be pregnant. No one can say without testing. You situation would place you in the non-pregnancy time but unexpected things happen! if you are late, just check it out.

Check a test: Easiest way to answer that is to check a urine pregnancy test. If you're pregnant, it will usually be positive by he time of a missed cycle.