Thank you for using Ask a doctor service from Doctor spring.
Firstly, calm down, and take deep breath. Relax , go for a walk outside and breathe some fresh air. If your head ache doesn't come down, then you can take paracetamol 500 mg now after taking your meal.it is a pain killer medicine which is available in all pharmacy over the counter without prescription.If still the head ache doesn't come down, you can take another dose after 4 hrs, sleep for some time and take rest. Take care.
Hope this helps, if you need further help, feel free to ask.