Implantation bleeding?

Sorry I know this gets asked a lot but just wanting some advice. I have very irregular periods. Last period being Decemeber 2015. Ttc just over a year. I've been working a lot of nightshifts over the past few months so have not been using ovulation tests lately. I noticed on Thursday morning there was a very small amount of blood when I wiped which continued until Friday night. Not enough to mark my underwear or anything. Then on Saturday I wiped and there was a lot more blood so presumed it was my period and used a tampon. On removing it there was no blood. I've been peeing a lot more and have really sensitive nipples which I have never had before. I normally don't have much feeling in them but have noticed over the past week they can be quite painful to touch. Don't want to take a test too early and be disappointed. Do you think this is just my period being awkward or perhaps implantation bleeding? Have never had a period like this before. Normally very heavy. Sorry for long post and thanks for reading 😊