What do you suggest if my left side of my gum close to the last tooth was swollen but then when i sneezed it popped and deflated , what was it ?

Abscess ?: That's what it sounds like. What caused it and what treatment is needed to resolve it needs to be determined by a local dentist. Just because you sneezed and it burst does not mean your problem is solved. Make the call....

Could be an abscess: so you need to see your dentist and get the underlying problem taken care of or it will continue to happen and it can cause worse problems with the gums and jaw.