Implantation Bleeding?!

Today was supposed to be my peak fertile day. Yesterday morning we BD and in the afternoon out of nowhere I started bleeding. I grabbed a the lightest tampon & decided AF came early. Went to the restroom & there were only three drops of blood then it flowed moderately like the toilet paper was full but no uterine lining. Just like that 5 mins later it completely stopped no blood to be seen. Could that be implantation bleeding? This month will mark a year since we started trying! 😍