Spotting or Period? Depo Shot...

[Lovemelc]

I had my last depo shot mid-March, and it expired June 15th. I started to have dark brown spotting (like tissue) on Friday July 22nd. It got heaver Sunday night, but still isn't filling up a tampon. It has been still rather dark and tissue-y, but it has dropped dark blood (fluid for sure). Today, Tuesday, it seems to be lighter, more like it was on Saturday, dark brown but with some bright red clots. Still not filling a tampon.
Is this a period? If so, can I assume I have ovulated? Or is this just spotting.
I had unprotected sex Saturday night and Sunday am (he ejaculated, the spotting wasn't enough to stop us ), and have had sex every weekend this month (without him ejaculating inside me). Is it early enough for me to be pregnant if this is not a period? Help!
I haven't taken a HPT yet...

 

[tmr1234]

I got this after a yr on depo but it was a few weeks befor my last shot ran out after that i got nothing at all for 12 months then it took another 10 months to get my BFP. On depo what i found out is any thing gose you will get all kinds of preg simps and it is just a nasty thing to have.