I Had Unprotected Sex On The 22nd Of June And

I had unprotected sex on the 22nd of June and I went for the emergency contraceptive pill 2 days after but the nurse told me it's not 100% effective so if I don't come on my period by the 13th of July to go back and do a pregnancy test but I noticed a tiny spot of brown blood in my pants on the 30th of June & it started getting heavier the day after the colour was dark red and now it has started to slow down and is now a brownish colour I'm not sure if it's a period because my period usually last up to 6 days or a week?