And a good midwife doesn't need to do internal exams to know when a woman is fully dilated, there are other signs, and as pp have said, your body will know when to push.
It sounds like you might benefit from some breathing exercises. Ask your midwife or google. Also, if you are under NHS care, it is unlikely that you will deliver with this midwife, however it's important that you get on with your community midwife too ( I assume this is the one you are talking about) so ask to see someone else.
Birth is very much coping with contractions, breathing through them, walking about to get baby to descend, sleeping when you can, keeping energy up. You might well be in the pool at this point. Then in the final stage, (in pool or not), you are breathing between contractions, and using them to bear down and push (same feeling as pooing). Baby will crown, at which point you will be at risk of tearing, and you pant to ease the delivery. Next push or two, the head will slip out, then the shoulders and rest of baby very quickly. I guarantee if you tear, you will either not know, or will very quickly not care.
Pre labour, perineal massage can also help.