Implantation bleeding

Hi, I'm 22and never been pregnant and had some questions about implantation bleeding. I was late for my monthly cycle, which is always 34 days, and then after few days after my cycle date i had some pinkish/brown discharge for a day or two. The next day I had bright red blood. It was very light and trailed off after a day. I was going to count this as my cycle but it was less than 2 days so i don't think it was. Now I only have a spot here and there. I looked up implantation bleeding and found women who have had heavy bleeding to spotting during this and didn't know if it was implantation bleeding or just a weird period. I took a Hpt after brown discharge and then another one after blood spotting. They both came up negative. I am going to take another test in a few days but was wanting to see if others experienced or their thoughts. Thanks

I thought I would also add that a few weeks ago several times after intercourse I had light bleeding and painful abdominal pain. I also had breast tenderness and was exhausted for no reason for a week. I know that some early symptoms of pregnancy are also PMS symptoms so I didn't know what to think about that either.