i don’t know what to do ??!!

i’m always early for my period and when i was 5 days late i began too worry i have been feeling faint dizzy and weeing a lot. i haven’t had sex without a condom though... i took a pregnancy test the came out positive with a faint line. today it seems a though my period has started? it’s a little heavy and red and i have a headache and my lower stomach hurts a lot my upper back hurts also (but this could be normal). is this normal ? i also drank a lot of alcohol on saturday night and people have said i look pale and i have been feeling sick. i am a very sporty person and excercise is hard for me now