The pills

I just wanna share something if this is normal or not. So me nd my bf had sex nd came inside me. I used to use pills the 21dayspills (BC) and I observed after we had sex during the last day of my period after a week i had brown discharge for about 2weeks and more. And now i got my period its 4x lighter than my usual period i usually have 6days of period but since this is my 1st period of taking pills i only had 3days. Is this normal or not? And everytime i take my BC i feel so ill or i want to vommit. Is this normal?