Bleeding with the implant

I'm on the implant and have been since June 9,2017. All bleeding stopped and I haven't had my period since may 8th. They had me take a pregnancy test before putting it in. I know bleeding is normal but I'm just bleeding out of the blue. I had what I thought might have been blood for a few days but then when I went to the bathroom it was 100% blood. I do have sex without a condom on now since I've been on the implant. Should I worry or is it still normal? Should I start using condoms until I stop bleeding?