Hello Sir..its Shristi Kamal Here..i Use To Have Sevier Headche..i

Hello sir..its shristi kamal here..i use to have sevier headche..i dont know i think alot..or coz of sinus..i dont know..and i feel very week....due to which my conc. Power is very bad.what should i do?? I am preparing for .edical entrance and i am unable to study..i think alot.. am unable to sleep..