Implantion or not?

so me and my fiancé think I might be pregnant . I had my normal period on December 9th and we had sex the 23rd because I wasnt aware I was ovulating. About a week ago my boobs started to hurt and get heavier and started to look weird and my nipples changed colors. Then I woke up thinking I had my period  but it was just really light pink only came of when I wiped. but the smorning it looked more like a period with more blood. Does that mean I'm not pregnant or do people sometime get more blood a clotting after spotting for a day and a half