Staying constantly in A/c is the root cause of your problem.are you a regular computer user if so it might be computer vision syndrome please use lubricant eye drops e.g. teardrop 2to3 times daily and rub ocupol d's eye oint twice daily on lids and do cold compresses with ice
Next Steps
Follow 20.20.formula ie close your eyes for 20seconds after every 20minutes.keep proper distance between eyes and screen wash your eyes with freshwater frequently and don't sit facing towards a/c blowers consume lots of fresh fruit and vegetables