How fast does gum disease progress? I think I might have gum disease. I'm wondering how long I can wait to see my dentist before it gets really serious..

Infection. Gum disease is an infection. I doubt if you had an infection elsewhere that you would put off treatment. As gum disease is progressive, the longer you put off treatment the more extensive (expensive) treatment becomes. .
Gum . Gum disease is called periodontal disease in technical terms and it is strongly believed that the progression of this disease is not linear but instead it progresses in burst and spurts with periods of quiescence in between. Periodontal disease should be treated as soon as it is discovered.
Don't wait. If you want to wait until it hurts, it will be too late. Most people with advanced gum disease never knew they had it.
Sooner not later. How long would you wait to take an infected splinter out of your finger? That is how long you should wait until you treat this bacterial infection. Gum disease does not get better with time; it gets worse. Treat it now. Try something that treats the cause, like the perio protect method. The easy to wear tray (10 to 15 minutes) is a treatment device at the beginning and resolves long term.
How . How do you know you have gum disease? Do you have bad breath? Are your gums bleeding? Do your teeth hurt when you chew? Do you have puss coming out from around your gums? You have to see your dentist immediately. The sooner you treat these conditions the less chance you have of loosing your teeth. Do not wait another day. Make an appointment asap.