Is it possible ?

My last depo shot start to run out roughly about 2 weeks ago fully running out this week . 1 1/2 - 2 weeks ago we had sex and for the first time in ages I didn't ask him to pull out . Few days after I got thinking and took 2 tests both negative . I've started spotting brown sometimes pink blood , servere nausea , tiredness , area around nipples colour slightly changing , cramp around and below c section scar . I had all these symptoms with my son and the night before getting a bfp I felt like i was going to get my period wore a pad and kept checking. I feel exactly the same tonight . Pic attached could it be implantation ?