Marina birth control

I got the marina the other day, didn't hurt going in and onky hald slight spotting for a few hours after... The gp told me it's not effective for 7 days after so just use condoms until than which is all good I restocked the other day. My questions are, did it hurt the first time having sex with the marina, did you bleed after, did it cause cramping etc did your o/h feel the strings?