Could I be pregnant?

Okay so I am 6 months postpartum, I am on the pill but this month I missed a pill the day before my fertile day, had unprotected sex the morning of my fertile day and then was on antibiotics for 10 days. I had spotting not long after that and then when it was time for my period I had a short 4 day period, the blood was brownish. My boobs have been itchy on and off, I’ve been cramping and tired and having hot flashes. Could I be pregnant? Should I take a test?