I can understand the distress you are through. The problem is suggestive of a condition called Phemosis. The foreskin opening is tight and prevents smooth retraction onto penis shaft. Normally the foreskin should slide easily on the penis. It is a surgical problem. With surgical correction of it, it can be completely cured. If not corrected timely, it can risk you for development of frequent penis skin infection and can cause discomfort while intercourse.