Should I take a test?

So, on November 20 my fiance and I had some really intense sex. The next time we had sex, it was really painful. We then had sex on November 29th. I had the mirena. A few months ago, I got the strings cut off almost all of the way because my fiance was complaining about them.. anyway. I went to the bathroom and I could feel the strings (something I couldn't feel since I had them snipped.) THE MIRENA ENDED UP COMING OUT. I still had a very slight period when I had it in. Well. My cycle started on the December 2 and lasted until the 4th. The 13th and 14th I had minor cramps and slight bleeding. The blood was in between a pink and reddish color. Should I take a pregnancy test? Was it implantation bleeding? We do have unprotected sex.