I had sex on first and second day of my

I had sex on first and second day of my period and my periods are irregular of 28 to 32 days my last peruod was 8 days long and now i am 8 days late
Im vomitting from last 2 days and my breasts are sore from last day
Today i observed a small blood drop on my underwear can i be pregnent or is it any thing else
Im feeling sleepy from last 2 days
My last period was on 4th sept and finished on 12th sept