Sir, there are a lot of reasons for eye swelling associated with pain, the most common being a stye.
The feeling of something moving in the eye could be due to dryness of the eye or a presence of a foreign body in the eye.
Next Steps
In that case, give warm compress as frequently as possible. To do the warm compress, take some warm water in a bowl. Dip a kerchief or a towel in that. Take it out. Squeeze it nicely and then give compress over the eyelid. Remember the water should be warm and not hot.
You can apply Zymar (gatifloxacin) eye ointment twice a day over the eyelid for 3 days. If it is a stye only, this should help you.
For the dryness, you can use Tear drops eye drops -1drop- 3times a day in the affected eye.
Health Tips
If your symptoms persist, it could be a foreign body in the eye. In that case, better to consult an ophthalmologist nearby as soon as possible.