Not sure what to think.. HELP!!

Well I was due for my af 28/2 it never came 2 weeks late I got a very faint positive on the Wednesday on the Sunday I got another very faint positive but darker both on clear blue. (Pink dyes. We're neg!) Anyway, then on the following Thursday I start to bleed I'm guessing it was af it was alot lighter in colour and watery than normal af but the amount there was normal ect.. now km looking ND thinking cus I still be pregnant inoe alot of people pregnant ND carry on having periods ect.

Look at my lines!