It seems that u have allergy
in your eyes. The feeling of sand inside the eyes associated with redness and itching gives a typical picture of allergic manifestation in your eyes. You should start with the following:
1> Lotepred Eye Drop
( one drop thrice daily on both the eyes for 10 Days ).
2> Pataday Eye Drop ( one drop once daily for three weeks ).
3> Lubricating Eye drop like "genteal" one drop thrice daily for 1 Month.
If you wear contact lenses
stop using the same immediately until recovered with the above.