Could I Be Prego? Last Actually Period Was 09/29-10/05. Started

could I be prego? Last actually period was 09/29-10/05. Started on thyroid and adderal prescribed from reg. Care physician mid November. My period at that point was already 18 days late. Around thanksgiving I spotted for a week with just staining. Last week stained for three days. Have had a lot of changes.. Constipation, nausea, mood swings, fatigue, and unusually cravings.. Like chocolate milk every day and large amounts.. Has to be whole milk and I'm lactose intolerant and I hate milk.. It is the only thing that helps with Nasea and it hasn't made me have diarrhea. Took a prego test back on the end of November and was negative. I also have a pituitary gland tumor which makes it more complicated. Should of started my period again already.