Help! Please!

So usually my periods are about 31 days apart. My last period was June 11th and I had pinkish white discharge on July 3rd just the one time that day then July 4th I had brownish spots one time that day and now July 7th I was clotting and bleeding through a tampon and getting abdominal cramps. Not severe cramps but still kinda painful. I tested negative today but I have been getting normal pregnancy symptoms before this.. nausea, tender breasts, headaches, and fatigue. I’ve never had these symptoms with my normal period before so I’m just wondering what’s happening!? Is this implantation bleeding or what is happening?? My normal period is still 5 days away