Implantation bleeding?

Help....In the beginning of July I stopped taking my BC, TriNessa, and since then have had two periods. My last period was September 18-23. The first week of October me and my partner had multiple sexual encounters in hopes to conceive. This would be a second pregnancy, and I had not been on BC prior to my first pregnancy. Wednesday October 11, I used he restroom around 6:40pm and when I wiped there was a very light pink strip of blood on the toilet paper. That was the only time I saw this on Wednesday. Thursday the 12th there was nothing. Friday, however, around 7pm I noticed there being some brownish looking discharge or blood. Very small amounts but has stayed pretty consistent since than up until now. I did not have implantation bleeding with my first pregnancy of any kind. I also read that it could be a possible sign for infection? Friday and Saturday (yesterday) I felt really nauseous and today it has ceased since then. What worries me is that this morning I took First Response pregnancy test and got a negative. And now just a little bit ago I used the restroom and when I wiped, there was this amount of mucus. I'm sorry the image is TMI. I'm hoping someone has experienced or is experiencing the same things as I am? I worry it may not be implantation bleeding since I read that implantation bleeding shouldn't last as long as what I'm experiencing.