Ttc and periods...

I had my daughter almost 7 years ago.. I had been on depo for 6.. I've now been off it for a year.. 13 months now since my very last injection... For the past 4 months now I've spotted on the 16th/17th of each month.. No real flow just enough to notice when wiping after the toilet.. This month the 16th comes around and nothing just blaring belly ache.. Then pain during urinating I became quite concerned had a sample taken into docs to tell me I had a slight infection but not enough to warrant any meds.. So I have religiously kept fluids flowing over past 2 weeks.. All symptoms have now gone and I feel slight uti free !  Yippeee! Tonight I have the worst migraine ever... And I have just been to the toilet before going to bed usual visit .. And wam... I've come on.. Just over a week late to when I spot.. I decided to freshen up and take a shower before changing into some fresh clothing and putting a pad on for the night as I was washing myself I noticed dark brown clots coming away... Now am I right in thinking this is totally normal post depo? I've not had this since spotting over the past 3/4 months at all.. These clot like things seemed to be quite tissue like.. Two about the size of my thumb? 

I've never experienced this don't know if it's worth a trip to get checked or if I'm just over reacting and this is the norm after depo leaving my system? 

Any feedback would be much appreciated sorry for the gross info