I never heard a patient screaming in all the time I flew EMS....but then perhaps our Med types are equipped to administer pain killers and protocols are in place to provide the patient with such meds when permissible for the kinds of injuries they have received.
Combative patients can happen....particularly with head trauma....but if they are secured properly....they can be handled.
When hauling Prisoners....we kept Guppy Making meds drawn up and ready for jabbing.....and briefed the prisoner exactly what his situation would be if he caused one bit of a problem. The antidote was also ready....but we did not tell them that.
As to low flying Jets....if you operate in a known low flying route then there is a risk of encountering the jets. I know first hand how big a problem they can be....but it would seem there is bigger problem if there can be no coordination between the Jets and HEMES. As the UK loves rules, laws, regulations, policies, and the like....it would seem the CAA and MOD could work something out for you.