Hi Friend I am Dr Bilal and I am an Ophthalmologist Welcome to Health Care Magic I would like to answer your question and your satisfaction is my goal . From the history given by you , you are having irritation and dry eyes because of contact lenses and the problem while in moving bus and under the sun may be due to infection / inflammation of cornea / conjunctiva . This may be due to poor fitting lenses . I would suggest you to use glasses for at least 02 weeks and notice any improvement in symptoms . In case of improvement , get a new pair of properly fitting soft contact lenses , new lens case , new lens solution . Meanwhile Use antibiotic eye drops / ointment , artificial tear drops . I hope that would help . If there is no improvement, then there may be a serious condition like infection, corneal ulcer, neovascularization, and iritis . In that case , consult an Ophthalmologist for definitive diagnosis of your symptoms . Wish you a speedy recovery and good health Good luck Best Regards .