8/9dpo

having the pinchy twingy pelvic cramps on left side.. I ovulated on the 17th at the latest... I had a positive opk on 14/15th and I feel a lot of pressure whenever I stand or sit and now it's one sided. I have a split uterus (babies only implant on one side) so I remember this feeling with my other pregnancies. If this is implantation or stretching when would I take a test? it's a moderate pain with movement. anyone have this with their bfp? 4days till suspected af. thanks in advance. xo.