Could I be pregnant? Please help.

Alinakisses

Ok so me and my boyfreind had unprotected sex 3 weeks ago, and now I'm experiencing sore breast, the sore breast litterly started a week after and hurt a lot more and feel a lot different and they DO NOT usually hurt this bad or long, constipation, verry moody, slight dizziness. Took pregnancy test (negative) but might be too soon to tell I'm supposed to get my period Feb 3,

Is their a possibility that I am pregnant