If the light bleed started on the 12th, then you would now be on CD8 (if not pregnant) It starts from the first day of your period. But, that doesn't explain anything anyway, because you've now got another pos OPK......
So even the MC/pregnant again theory doesn't fit, because you wouldn't have OV'ed again.
It is almost as if you have been pregnant all along, your hormones started to build up, then decreased, then built up again.....?????? That just doesn't happen, does it?
Well, all of this second guessing isn't going to help is it? I think you need to go back to the surgery tomorrow morning - don't just ring for the results, go down there - obviously if the results come back pos, then you do need to insist on a scan, because you'd have no idea of the EDD, and equally, if it is neg, you need to camp there till he gives you answers, seriously, this can't go on for much longer, put your foot down, and tell him you're not leaving until he does something to try and work out what is going on, it is the only way you are going to find out anything, and put a stop to all of the worrying and pissing about!
What did you say when he asked you if you felt pregnant?