Feeling sick even after period

I need an advice on what to do

I’ve been feeling sick days after my ovulation

Headache, nauseous and vomiting, cramps, stomach pain but saw my period( this usually happens whenever my period is about to start) but now period has ended but I still feel same, no Changes at all except that the vomiting has increased to the extent that nothing that enters my stomach stays, I get scared of eating now cos I know it will end up leaving my stomach.

Please what should I do?