Pregnancy or nothing?! I’m really starting to panic.

So I am on the pill, but recently it’s given me spotting between periods after using it for 1.5 years. I always take it on time or an hour later. 5 days before my withdrawl my boyfriend and I had unprotected sex and he didn’t finish in me. I usually get spotting two days before my withdrawl and I have gotten notning!! My withdrawl should be tomorrow but I have had no signs, no cramps, no discharge just an ongoing two day headache. Could I be pregnant or should I expect my bleed? I will get a test if it doesn’t come but I wanted opinions