Morning after pill

On Nov 19th I took Plan B a couple hours after having sex. He didn’t use a condom but he pulled out. I got my period around normal time and it came with cramps and heavy bleeding. It lasted from the 1st of December until like the 8th of December. I should have my period this week but instead, yesterday all I got was a dark brown stain on my underwear, like old blood. I had a headache and some light cramps yesterday too. I woke up this morning to check if my period came and nothing! Not even one little drop of blood. I’ve been having lots of bloating/some weight gain? and peeing a little more than usual. I have not had any nausea/vomiting, sore boobs or any other pregnancy symptoms. Should I go take a test? Or what do you think is wrong?