When can I take a test?

So I have pretty irregular periods and my partner and I are trying to conceive. We had sex 28th August and tonight, both times without protection. I have been getting symptoms really early but then found out I have the Flu (not COVID) I am unsure if it’s the flu that was making me feel some symptoms or I’m pregnant. When is the best time to take a test. I finished my period the 26th. Unsure on my ovulation days. Starting to log so I can see. Also tonight I had pink discharge and I know this can be a sign of implantation so I’m unsure! My period also randomly stopped. It was shorter than any period I’d ever had before. It became lighter the day after we had sex, then stopped after that. Don’t know if that has anything to do with it.

How long should I give it before I take a test?

Any advice would be great! Thank you!