Irregular periods

So I have been on my period for about 11 days now, or what seems like my period. I am usually on for about 3 days with spotting for about 2 more days afterwards. My period started off with really dark blood this time for the first 3 days and lighter than usual and then continued and got lighter in color for a few more days. Fast forward to now I wont bleed for a while throughout the day but then I wipe and theres a substantial amount so i use a pad/tampon. I do have to say that the previous month i took 2 plan b's but I have taken them in the past and they havent made me bleed this long. Anybody experience this before?