WOW, Congratulations
As far as the tape goes, it sounds like you are allergic to it, you might want to try a cloth tape called Medipore, the same thing happened to me (the tape, not the pregnancy) lol, but the Medipore seems to be working well for me, and as far as "how it keeps happening" well, there is this little bird and there is a little bee...
Good luck to you with everything