Very light brown discharge? Implantation bleeding?

Zoe

Today I had very light brown discharge and nothing since. My periods are all over the place as I don’t have a period for months and they have been like that since I was on the pill but I came off the pill a few years ago. I’m not sure if it’s a start of a period or if it’s implantation bleeding. I haven’t had no other symptoms apart from missed period of course but I haven’t had one for months and I was sitting down talking to my partner the other day and I went dizzy for a few seconds. Can anyone help and tell me what they think it is? I attached a photo to show what it looks like. Sorry for TMI