I had periods on 27th september. On 6th october, my boyfriend ejaculated on my stomach. It went down till my thighs and near pubic region. I washed off immediately. I was worried so I took an ipill the next morning. Today I noticed a little brown discharge from the vagina ,just one episode, it was scanty in amount. My periods are expected on 26th october. I have normal 28 days cycle. Is this normal or should I do something?