Hi, I am Dr.Shreyash Mehta, MD Community Medicine
I understood your query I hope my answer will solve your query
As you told that you had unprotected sexual intercourse with your boyfriend a week after your menstrual cycle.
You say that you throw up yellow sour fluid, that is mixture of the food you consumed and your gastric juice.
It can be due to some
anxiety, excess intake of spicy food or a manifestation of early
pregnancy. Morning sickness(i.e.
vomiting in morning ) occurs after 4th week of pregnancy and can last till 12th week.
Excessive sleepiness may be due to some excess work,
depression or may be due to pregnancy.
The one method to diagnose whether you are pregnant or not is by doing urine pregnancy test through kits available in market.
The second is that you get yourself examined by physician/gyneacologist.
For the preventing vomiting you can take Tab.
promethazine and you should avoid spicy, fried and food with high fat content. You must take rest.