Ouch! I've had something similar happen to me last year. First, I noticed some bleeding, but it developed a large scab on my shin caused by the bleeding because of Calciphylaxis ulcers, or so I was told. Anyway, I ignored it at first hoping that it would go away if I bandaged it. Over time, it became quite painful, that it affected how I slept and walk, etc. So, I went to the clinic to check it out, and I was told that it was a ulceration of the leg. I was told to have it checked out at a hospital that specializes in wounds, because it was this large painful wound I had on my leg. So, yeah I went for the treatment and it took about two months for the wound to completely heal. I don't know if this is exactly how it is for you, but it may be similar. Go have it looked at, because I hear it could be fatal if left untreated for so long.