Bleeding after missed pill


Hi everyone. I posted yesterday but didn’t get much of an answer. Just checking again. I missed 1 of my birth control pills on Saturday. Then on Sunday I took the Saturday pill along with Sunday’s. I’ve been spotting since then and the last 2 days it’s turned into basically a period. I’ve been on the pill forever and take it religiously and normally never miss one so I’m unsure as when this bleeding is going to stop. I’m not due for my period for another 15-18 days. It’s my own fault, but I can’t believe that after missing one pill I’m bleeding like this. Any advice/experience would be great. Thank you!