hi nik, sounds promising for you hun. fingers crossed AF doesn't arrive and the BT on weds is a BFP. it is so hard this last week waiting. it really can do your head in. try and stay as positive as you can. i have only ever had brown spotting from the crinone irritating my cervix.
there are a few threads in BB on implantation spotting (in the conception threads i think) where you may get a bit more info on your symptoms.
we are holding your hand hun. xx