What causes gout, and what are the symptoms 1 have this severe pain in my knee for two days now, and I think it could be gout.

High uric acid. Most commonly high uric acid can cause gout. Certain foods for example alcohol and shell fish can cause high uric acid and "gout attacks." a simple exam and testing can diagnose if you have gout, and then you can get the proper treatment. Good luck.
Gout. May or may not have elevated utica acid levels. Definitive test is joint fluid analysis in polarized light for negative birefringent needle-like crystals that are causing the inflammation and pain.