Having a tight foreskin, I prefer her to start with my foreskin nipple, gently insert tongue and use it along with her lips to work the foreskin back super slowly, so I can feel the skin being stretched as it strains against my blood filled cock head! Ever since forced retraction as a child and the pain, I've had a thing for tight foreskin retraction.
How small is the opening in the foreskin? Can you see the meatus? If so, you may start with a Q-Tip to start the stretching process...if bigger, then try to push the glans through the opening by pulling back on the foreskin...there should be some discomfort, but not too painful.
Your glans is VERY sensitive when first exposed and will become less sensitive the more you wash and touch it. If you don't yet, you come to love your foreskin and the sensations it will bring you. Thank you for sharing your story, as I really get hard reading others experience at the doctor's office. ESPECIALLY ones involving retraction of the foreskin!