Why has my eye been itchy for two weeks and been using eye drops and it has not been working?

Allergies. Eye itching is usually secondary to allergies. What drops are you using. If they are just artificial tears they may not help your symptoms. There are a number of allergy drops available that are very effective in treating the itching. Unfortunately none of them atually cure the allergy. The only way to do that is to remove what ever it is that you are allergic to from your environment.
Agree. Would also get to an allergist to find out what you are allergic to in order to help with avoidance and provide the best medication(s) suited for your allergies.