I took a preg test 3 weeks ago as period was late, boobs sore and just 'felt' different, but it came back negative. Couple of days later I got my period, well definitely bled but not much (although I never have very heavy periods anyway) but 3 weeks later I'm still feeling funny - have had cold for 10 days which can't shake, even though usually I fight things off quickly, as if my immune system is weakened, boobs sore and seem bigger, feel ratty and argumentative and needing to wee several times an hour.
I know you can't have a proper period whilst pregnant, but could it have been implantation bleeding?