I can understand your concern but your question is very incomplete, you should have mentioned your power and also from how many months/years you are using those.
When was the last time you got your eyes checked?
What kind of job is yours?
Does it involve sitting in front of computers for long hours?
I suggest you repost the question will these details or consult a ophthalmologist for further help regarding this.
You may need a different pair or glasses as the power might have changed. Put artificial eye drop preparations like ontears three to four times a day in both the eyes.
Give your eyes frequent rest.
Drink lots of water.
Cover the eyes from harsh sun.
Dr. Anil Kumar Jain.
Eye strain can be due to a lot of reasons 1.long hours of TV,Laptops
3.general health conditions and fatigue
4.change in refractive error
Please get a complete eye check done including schimmers test and TBUT
Send the detailed reports