A short rest consists of at least an hour of no strenuous activity. You can regain HP during this time by spending your hit dice. Each die spent like that let's you roll the die, add your CON mod to the result, and gain that many HP back. You regain up to half your level worth of hit dice after a long rest.
Anyway, I hope you feel better and that you get some medicine soon.
Short rest rules are on page 186 of the Player's Handbook, but I'll explain them here:
If a character rests for at least an hour they can roll a number of their hit dice up to their level in that class (so if Kylessa, a level 2 wizard, wanted to recover some HP she would roll up to 2d6) and add her CON mod to each die.
So if Kylessa rolled 1d6 and got a 3 then she would gain 4 HP.