This problem may be due to Wax in ear/ or may be Eustachian tube blockade
Kindly follow advises given below
1.do not pore anything in ear
2.avoid water entry
3.As you need internal examination of ear by Otoscope so kindly consult ENT surgeon
Suggestions offered by doctors on Lybrate are of advisory nature i.e., for educational and informational purposes only. Content posted on, created for, or compiled by Lybrate is not intended or designed to replace your doctor's independent judgment about any symptom, condition, or the appropriateness or risks of a procedure or treatment for a given person.