Period and then bfp??!!

I just posted on faintlines but... I had my period a week ago it lasted five days and its been two days scince then ,I had sickness this morning and my SO had mentioned that I should test , he was at work all week so I didn't much see him to tell him I was on my period , anyway he went to the shop and bought me one I told him he was stupid because I had been bleeding but when I took it I thought I noticed a faint line ... If anyone could tweak or tell me what they think that would be very much appreciated