What Causes Blurrness Of Vision And Sensitivity To Light On Right Eye?

I have a problem on my right eye - my vision is blurred, i have sensitivity to light, i cannot bear the light and stay infront of computer, i always feely sandy gritty feelings that really makes me irritate. Everything starts when I got medication for my ulcer and the medicine I'm taking is so strong that gives me too much headache and paining for my left eye. Then when I stop taking the medication i noticed that vision changes most especially my left eye, I experienced eye twitching for how many days. my eyes become sensitive to light, always tired and dry. Then I went for eye specialist they say that my grades for my eye changes and become high most especially my left eye and got astigmatism where in before i dont have astigmatism. As i wait for my new glass i decided to wear my contacts first, but one day when i used my contact my eyes become irritated. The next morning when i wake up eyes swollen and paining already most especially the right eye. I went to doctor (general practitioner) for check-up and the doctor says i got conjunctivitis, so he prescribed me drops, antibiotic ointment for my eyes and some tablets to drinks for 7 days. Its been going to 3 weeks already and still my right eyes is not normal. I already using my new glasses with new prescription but my right eye is really blurred and sensitive to light, i need to wear sunglasses when im going out under the sun, it makes my eyes cry plus the sandy gritty feeling. Please help me...