Not sure what is going on

Hi I was wondering if anyone has had something like this happen and ended up being pregnant .

my period was due 9/10 but didn't come until 12th. Just before it came I had a large amount of clear snot like discharge come out a bit like your plug.

then had a slightly lighter period than normal that lasted the normal 4 days.

A couple of days after I'd finished bleeding I had a very small amount of brown colo discharge/blood for a couple of hours and now nothing.

I have been getting cramps and slight back ache . 

Could the brown blood be implanting or am I clutching at straws here?