It could be a problem of Phemosis. The foreskin opening is tight and prevents smooth retraction onto penis shaft. It is a surgical problem and can be corrected. Depending upon the degree of constriction at the foreskin opening the management can be decided. Circumcision is the definitive treatment of it.
Next Steps
Kindly visit a nearby general surgeon. He can conduct a detailed physical examination and evaluation.
Health Tips
Don't worry. It is treatable.