IUD & implantation bleed experiencers I need your help!

Rebecca
Had my period on 05/04 (in UK so USA swap it round!), IUD 18/04, another period on 20/04 presumably due to drop in progesterone from the IUD coming out. Took opk, peak days were 27 & 28. Had cramping last two days on and off and now had a small bit of spotting this morning, pink colour. Anyone have any experience of having an IUD in place and then periods close together after having it removed or could it be an implantation bleed even though it is quite soon? What have people experienced before  please? Thanks! 

Vote below to see results!