Implantation Bleeding or Early Period?

My husband and I have been trying to conceive for 6 months now, we already have a 3.5 year old boy and in 2014 we lost a baby at approx 10weeks. 
My period is due on Boxing Day but this afternoon after going to the bathroom when I wiped there was a pinkish bit of blood when I wiped so far there has been no more. 
I don't feel crampy but have been emotional which I can be in the lead up to my period but I think I'm a little bit more emotional than normal. 
My periods can vary, one month I was 6 days late, then it was 2days early the next month and the last few months I've been a day or two early. 
What are your experiences do you think I'm just getting my hopes up this is a longed for baby!! If you had implantation bleeding how long did it last did you have other symtoms?xx