Welcome to HCM.
It is due to severe allergic reaction
after garlic application.
lotion and steroid
containing skin cream.
Also take nsaid
to subside pain,inflammation and levocetrizine to subside allergic reaction under guidance of your doctor.
You can cover it during college hours,it also protect against sun light.
Avoid direct exposure to sun light.
Drink more water and other liquids.
If it is recurrent than you have to apply sun screen lotion during exposure of sunlight.
Keep in touch with your treating doctor.