weird cycle

Heather
My last cycle was 34 days. Usually I have short cycles, 24-26 days. My period was nearly a week late, and I was convinced that I was pregnant. I took 2 tests and got bfn's so I decided to wait it out. When I finally got af, I spotted for 2 days and thought it was implantation bleeding. After the spotting, I had heavy bleeding, more than normal. I had to change my pad and tampon every 1/2 hr. I always need to wear a pad and tampon together. I'm just wondering if this is a chemical pregnancy? It's not like my other cycles, and the heavy bleeding freaked me out.