Usually the eye drops will have the function of moisture the eyes. That is why a lot of people with dry eyes will use the eye drops to treat the dryness of the eyes. The reason that your eyes feel itchy may be caused by the allergy from the eye drops. You should stop using the eye drops and have the good rest for the eyes to get the recovery.
First, calm down and make sure that your eyes don't feel any pain. Then you should look at the mirror to see if there are any foreign stuff in your eyes, and really roll your eyes to see if there anything come out of your eyes, sometimes you may not feel irritated yet. After such simple exam, don't worry. As the eyes in dry situation, they will constricted the tiny blood vessels around your eyes. Now, you use some lubricated drops to relax them, it is normal that you will feel itch when the blood circulations recover. Remind you of checking your eye drops production date, if it expired, oh my dear, do not hesitate to see your doctor, he/she can help you.
I think you may get chronic conjunctivitis which will make your eyes feel itches, and some eyedrops are invalid. There are also many factors lead to itchy eyes such as mycotic or bacterial infection, chemical substances enter the eyes and so on. I suggest you go to the hospital to buy some eye ointments which have good method to itch. In addition, try not to rub your eyes, even if they itch.