Hi, A Month Ago I Felt Like A Foreign Object

Hi,
A month ago i felt like a foreign object was in my right eye (upper eyelid). i did everything i could to try to remove it but failed. i went to the clinic and after checking my eye the doctor said there was nothing in it but there was an inflammation. He gave me dexamethasone to apply 3 times a day. It did not help as i could still feel like there was n object in my eye, even though it would come and go. so i went to a second clinic where after examining my eye again, they said the same thing that my eyelid was inflamed and had some small blisters. They told me to continue with the same dexamethasone and also gave me an ointment (tetracycline) which helped and eventually the inflammation was gone. However, this morning the inflammation came back but this time in my left eye (Upper eyelid). It feels like something is in my eye and i cant work because i cant even open my eyes for a minute.
My question is, what is causing the inflammation and what can i do to avoid this. should i continue with the same medication as before?