When should I test?

I just got off the pill the end of December and had my period Jan 4-8. I’m not sure what my cycle is as I’ve never had a monthly period. If it’s a 28 cycle I should have started my period last Thursday and didn’t. I took a test last Wednesday and it was negative. I have been extremely moody, headaches often, nausea, and now a I have a light pink discharge. Am I starting? Should I test again? I’m new to all of this! Thanks in advance!