@Ebbie_Anne
I know when I need, as opposed to want, an enema when my rectum feels ‘packed’ with poo and sitting on the toilet seat and relaxing, and even bearing down gently, doesn't start the poo coming out. I learned to never stain to poo as that can cause or aggravate hemmis.
I also know I really need help if those symptoms are combined with difficulty in starting to pee while sitting because, in a guy, a rectum full of poo can press against the prostate gland which narrows or even occludes the urethra.
This is especially true in hospital, if one is confined to bed and has to pee in a urinal and poo into a bedpan. In fact, despite my conversations with the doctor tying to convince him to order a bag enema to empty out the poo, I've wound up having the nurse insert a Foley catheter to empty my bladder two or three times. While that makes me pee uncontrollably, it does nothing to relieve the discomfort of rectal fullness.
IMO, any time the poo doesn't start promptly and easily when I sit on the toilet seat, it's time for some water. That doesn't mean a full bag of warm, soapy water. I've found that an 8 Oz Adult bulb syringe full of plain warm water, given and held while sitting for a few minutes, is often enough to get an easy poo started