missed period for 3months but my tubes are cutand now im spotting ....?????

ok , ive had my tubes cut and burned 8 months ago after i had my twins, i had a normal period for the first 4 months then i missed it for 3 months o_O when i finally got it, it lasted for about 8 days and was extreemly heavy (i never go more than 5days and its always light to moderate) i thought nothing of it since i missed for 3 months i figured my body was just making up for the lost time from going so long with out it .  then i was steady again for 2 months but than it came late last month and was VERY heavy but lasted only 3days and stopped, no slow down then the left overs like a normal period , it just stopped. well that was bout 3 weeks ago and today i woke up and went to the bathroom and was spotting, but dark color not the redish period kind, but a dark brown color dripping like heavy period.. im thinking no bueno something has to be wrong since it was that color and now i have nothng , it only came out while i was sitting there on the toilet. ive been moody and having extreem migranes on and off for about a month now  (i never get head aches let alone migranes) i want to go to my doc but i dont want to pay 40 dollrs (my co pay) just for them to tell me its normal im overreacting and nothing is wrong . i dont really knw what your body is supost to be like after your tubes r cut, like if everything should still resume as normal or if things will be a little different (hormonal and menstration wise) .... any one have any suggestions , same issues or experiences ??? ide appreciate the advice :)