Missed period??

First things first I'm on birth control, I use Feanolla mini pill (a progestogen-only pill) and a couple of days ago I completely forgot to take 2 pills so I missed Sunday and Monday... (27th and 28th) me and boyfriend had unprotected sex around the 25th but he pulled out completely a few minutes before he finished... I'm just confused as to whether the mini pill has stopped my periods as my doctor did say it could possibly stop them or could I possibly be pregnant?? I'm just getting worried, should I buy a pregnancy test??