Weird discharge after plan b?

Hi there!!

I had unprotected sex on 6/29 and then took a plan b that night since I was starting my ovulation fertile window the next day, the next day I had sex again and he came in me again, I didn’t take a plan b for this time.. about a week or so after I had back pain and the worst breast tenderness lasting days, the last few days though I notice some clear sticky discharge with little brown in it, today my discharge is a light pink/orange tint but mostly pink, and feeling a little bit nauseous I am due to start my period on Sunday and took a test today which was negative but thought it might be too early to read accurately and also I do know it could be the plan b, I have taken them before and never experienced these symptoms with it … help please and thank you in advance!

Update - today it has gotten a little heavier, it’s still pink not red at all