First of all, it is advisable not to donate blood when you are having an acute infection. It will not be of any use to the recipient & may put him to further risk.
The symptoms as mentioned in your post indicate that you might be having Acute Tonsillitis
1. Gargle with warm salt water to relieve throat pain.
2. Analgesics like paracetamol
3. Antibiotics depending upon culture & sensitivity reports to remove the causative organism.
4. Antihistamine preparations can also be used to provide symptomatic relief.
If symptoms still persist...it will be better to consult an ENT specialist
Meanwhile...avoid taking cold
food & drinks, maintain adequate hydration & take soft, non-spicy foods.
Wish you good health & a speedy recovery.
Thanks & take care.