Don’t know what going on?

Don’t know when I’m due on my period it’s just a rough guess. I think I last came on nearly 4 weeks ago . The other day when I woke up after the toilet I notice A slight colour when I wipe then for 2 days in a morning I would wipe it would be a little pink and then it went to a brown colour only when I wiped then it went away. Woke up today it was the same had a bit more pink on the paper this time. Could this be implantation bleeding.