Could I be pregnant?? Mom just wants a margarita.

On 12/3-12/10 I had a normal period. I have sex on 12/24 unprotected. On 1/3 & 1/4 I had a “period” that was superrrr light, pinkish and brown. I have had a few pregnancy symptoms like cramping on one side, nausea, fatigue, back cramping. My next period is due in about 18 days.... could I be pregnant?