It's typical for you to feel very relaxed, and a bit detached.
I'm an erratic subject. It sometimes works on me, sometimes doesn't.
Medical hypnosis works - I've seen someone get their aorta patched with hypnosis as the only anaesthetic. The patient was calm. almost drifty, chatting with the MD who was doing the hypnosis, and reporting feeling "pressure" as the surgeon sliced him open, rummaged through his innards, patched the huge artery, and sewed everything back up. **added - the OR staff were all told how to act. If we had ruined the trance it would have been really bad! We were silent, mouths taped as a reminder to not say anything, working from hand signals, moving calmly, and there was some white noise playing to cover any clinks and rustling cloth - the only people talking were the patient and the hypnotist.
And, a few of the OBs habitually used hypnosis on the women in labor - I watched one of them take a frantic young woman he had never seen before and get her calm, comfortable and focused in about 5 minutes ... the guy was really good! She was brought in in mid-stage labor, no pre-natal care, and had heard nothing from the women around her but how agonizing the process would be.
I use it often on others, at a low level, for calming and pain control while I'm working with skiers with injuries. A "light trance" state is easy to place on someone else, especially if they are looking at you as the solution to their problems ... they want me to make them hurt less, so I do it. No formal declarations, no counting, it's all voice and attitude. Much like soothing a frightened horse.