It seems that you are suffering from common cold. The competition and the lack of sleep coupled with decreased nutrition could have caused a decline in the body immunity.
The common cold is a self-limited contagious illness that can be caused by a number of different types of viruses. The common cold is medically referred to as a viral upper respiratory tract infection. Symptoms of the common cold may include cough, sore throat, and nasal congestion. Because so many different viruses can cause a cold and because new cold viruses constantly develop, the body never builds up resistance against all of them. For this reason, colds are a frequent and recurring problem.
1) Take Tab. Tylenol to reduce the fever and decrease the swelling over the throat.
2) Home treatments such as gargling with salt water, drinking warm tea may help relieve discomfort and reduce the inflammation.
3) Take over the counter nonprescription drugs Tab. acetaminophen 250 mg twice a day or Tab. Ibuprofen to relive the pain.
4) Only as a last resort antibiotics specific to the bacteria can be tried. Usually Tab. Amoxicillin is used. You will need to get a throat swab and culture done before antibiotics.
5)The virus that causes mononucleosis (mono) can lead to tonsillitis that is as severe as tonsillitis caused by bacteria .If you develop swollen glands, consult a doctor for mono.
6) Take tab. Cetirizine to reduce the discomfort and itch associated with the Common cold and flu
If the symptoms do not reduce in 3 weeks consult a general physician as it may need through physical to find the nidus of infection.