HELP ME !!!!!

Okay so I wasn’t 100% sure but can you get pregnant on your period ??

I’m on the pill so I don’t get pregnant but I only have the 21 day pill. So I take it for three weeks then stop taking it while I’m on my period, however, I’m sexually active and have always had sex on my period. So this month I haven’t taken my pill for 5 days now and still haven’t come on and I’m shitting myself... I’m having really bad cramps, feeling really sick in the morning and throughout the day, feel really tired but then can’t sleep at night.

Am I pregnant? I’ve made an appointment with my doctor but only next available appointment is Thursday the 4th October. Should I buy a test before then to be sure ?

Please help me and give me any advice you can !!

Thank you