Feel pregnant but bleeding......?

My partner and I decided to start trying for a baby in August so I came off the patch immediately. I was lucky enough to get a period 32 days after coming off, and have subsequently had another period 32 days after that. I am sure I am ovulating because each month I have felt ovulation pains, first period on the right side, second period on the left side. Throughout the entire past month we have been having unprotected in the hope that I would get pregnant. My ovulation day was Friday 7th Nov and my next expected period is 22nd November. In the last few days I have been having lower back ache, extreme tiredness and forgetfulness (very unusual for me because I usually have the memory of an elephant!). I feel different and wondered if I could be pregnant. Then yesterday morning I woke up with cramps and when I went to the toilet I saw spots of blood on the paper. I was over the moon thinking it was implantation bleeding. However, as the day went on the bleeding got heavier. It certainly isn't the spotting that is usual for implantation bleeding, however, I can't believe it is my period as it is a week early and considerably lighter than what I have ever experienced before. My usual periods (for the past 15 years) have been very heavy and required medium to heavy flow tampons. The blood I am experiencing at the moment wouldn't need anything bigger than a light flow tampon. I am very confused at the moment and I know people will say the easy way to sort this out is to use a home pregnancy test but it is too early at the moment to pick up the hormone. I will book a doctor's appointment tomorrow but my surgery are rubbish and it is unusual to be able to see a doctor within a week of ringing! Argh! Has anyone else experienced anything similar and got a positive or negative outcome. Thank you :)