Implantation bleeding?

Hey,

I have been feeling very sick for the last week or so and have been getting very bad back pain. I took a pregnancy test a few days ago and there was a very very faint second line. I am now 2 days late for my period but today I have had very light bleeding. Normally before my period I get really bad cramps to the stage I can’t move then come on very heavy straight away, but this is light and I have had no cramps. I was just wondering if any of you think this is implantation bleeding or just the start of my period?