Side aches and pinkish discharge

Hi friends. I've been experiencing an achy feeling in my right side for over a week. Sometimes, my abdomen has this funny hot, almost-burning feeling. I just went to the bathroom and had a glob of discharge that had a tinge of pink throughout it (TMI, sorry). Could this be implantation bleeding? I really don't think it's period blood, but I'm wondering if it's from sex last night (hubby and I were on a trip and forgot lube; I ended up a little chafed). AF is due in 2 days. I don't want to test until after my period is late, because I don't want to waste another test, but this month feels different. Any thoughts or similar experiences?