By order of your question;
1. I am no doctor however, crystals start forming once uric acid is high enough to hit saturation point (click the uric acid levels chart on the right) When these crystals do form, they still need time to accumulate in joints and cause problems. How long does that take? The general short answer is years.
2.This depends on your uric acid levels to start with. Generally, diet only can only help with gout sufferers who have ever so slightly raised uric acid. Stopping alcohol and certain purine rich foods generally drop the levels just enough to get you back into the safe zone without drugs. If you are past this margin significantly then diet alone will not help. You need to get your levels checked and only from there can you take an educated decision.
3. Genetic tests can be done to check your uncle and your DNA to identify certain links. I believe this will require specialist doctors / centres. I am not too sure on how it can be requested where you are and it may be costly.
Do you have any blood disorders?
As nobody says, try and find a good doctor and get a second opinion, there are various other tests that you can do to help diagnose gout.
Also remember, depression doesn’t help either and it is very important that you try and tackle this too. We are all here to help Rich. Good luck.