Thick Brown Discharge

[SallyK]

I recently started taking a high dose birth control called Jolessa, it's the off-brand of Seasonal, and I am only supposed to have a period once at the end of every three months.  I recently started on my third pack and I noticed some dark spotting, when I heard about spotting I thought that I would only bleed a little bit for a couple days, but it is lasting as long and is almost as strong as my normal period would be.  The only thing is it has been a dark brown and today I noticed a very thick, sort of glob.  Is this normal?  I have had unprotected sex before and I think the last time I did was about a month ago.  Yet, I generally remember to take my pill at the same time everyday, I have forgotten only 3 or 4 times, but I remembered to take it a couple hours later...Please Help!