I Had Protected Sex On The 2nd Of July So

I had protected sex on the 2nd of July so I was expecting my period on the 8 of July since my period are regular but it didnt come it came on the 13 July and it started brownish then it became heavy and lasted for 4 days and ursually it last for 7 days.after the period I noticed that my breast and aerola are getting big so I bought a pregnancy test on the 28 July but it came negative,im confused because my breast are still getting big.so was asking if I could be pregnant?