Two small bleeds

Hi can anyone help. i was due on my period thursday the 5th feb. on the tuesday i had small bleed only once when i visited the toilet then i missed my period an then on sunday i had another small bleed again only once an it was a brownish color. my periods are usually ever 28 days so i am really confused of whats happeneing. i took 3 pregnancy test an they were all negative. i also had a miscarriage 3 months ago but my period last month was back to normal
does anyone know if i could still be pregnant