Hi, In December My Period Was Only A Day And

Hi, in December my period was only a day and a half long I am very regular and they usually last about 5 to 6 days. The month of January is at its last day and I haven't gotten my period. I feel like bubbles in my uterus I don't know how to explain the popping feeling I have. I did a pregnancy test about a week ago but it was negative. Could I be pregnant?