It could be a problem of Phemosis. A condition in which the foreskin is very tight and prevents smooth retraction onto penis shaft. It needs surgical correction. If not treated, it may cause painful intercourse, frequent foreskin infections. It is completely curable.
Next Steps
You must consult with a general surgeon. After physical examination and evaluation of the severity, further management can be decided.
Health Tips
Don't worry. It is a common and treatable.