Unusual Changes in discharge

[Unsureperson]

My partner came to visit and we had sex about 5 days before my period was due. I use the pill as contraception but I forgot to take it on the day we had sex and the day after but then took it regularly afterwards which hasn’t been and issue before. I noticed weird thin discharge and a slight itch which is common with Bacterial vaginosis. This doesn’t surprise me as a had a significant bladder infection about 2 months ago. But now my period is due I’m having more painful cramps than usual and my discharge is now clear and thick with brown/pink flecks? Am I pregnant and if taking a test should I wait until the discharge returns to normal because I’ve heard that during Implantation women usually get a false negative.