The differnce between ballooning and edging is , while you edge you work urself to a stiffy and kegel just before you cumm. It’s more like practising to stay off ejaculation while at the same time getting the sensations of an orgasm. Ballooning is a little different. You wank off till you reach the point of no return(PONR). Just when you reach that state you stop stimulation of the trigger zones which otherwise would start the Emission phase. Instead soon after you reach the PONR you start to massage the non trigger zones in order to maintain the erection and at the same time stay off the emission phase.
Generally what happens is once you reach the PONR and you stop stimulation, your dick kinda starts to become soft. Ballooning( massaging the penis at the base) allows for enough stimulation to maintain the erection but not allow you to ejaculate. Hope this clears your doubt.
My opinion about kegels is that it’s BAD. I’ve been using kegels to ward off ejaculation and believe me I had become more responsive. I just couldn’t last like I used to. I really had to re train my nerves not to kegel. It will take sometime for you not to kegel when you are wanking off but let me tell you that it’s worth the effort. Just focus on not kegelling. It’s tough initially cause you are so used to it.
I’ve been just Ballooning for the past few days and I feel it’s an excellent way to keep yourself from ejaculating.
PS: Retainer I’m not sure if you are ballooning since you are kegelling when you reach PONR.