Implantion bleeding

My last period finished on the 15th of May, I had a tiny amount of pink blood/discharge last night and today - waaaaaay waaaay too light to be my period, I’m usually heavy. Could this be implantation bleeding or has it been too long? (Obviously I had unprotected sex around the time of ovulation which was a couple of days after). I had implantation bleeding with my baby girl but for the life of me I can’t remember when i experienced it!! I was due on my period yesterday... We are TTC for our miracle baby number 2! 💘