Where can I get my diaper changed?

Before I start I would just like to say that this is a serious question. I'm not trying to be funny or something like that. I would like serious responses please. First of all I am a 15 year old male in the United States. I am incontinent and have to wear diapers as I cannot hold my bladder. So far I am incapable of changing my own diaper. Someone in my family will take care of it for me easily. I have tried countless times but always end up either ruining the diaper or not doing a good enough job to secure it on me. I am trying to learn from my family how to do it on my own as I would love to do but it has proven to be very difficult. My family is able to change me when they are around. However, if I am somewhere on my own and I wet my diaper, I have no way of changing myself. I have tried just going to a bathroom and changing it myself but this has always resulted in embarrassment. If I try to ignore it and just go on, I end up wetting my diaper again and having it leak all over me in public. I always carry diapers with me but I have to end what I am doing and go home just for a change. Then I have to go all the way back and continue what I was doing. I would love to know if there would be ANY sort of place I could go that could help me out when I am in public and need a change. As soon as I can do it myself I will be free of this embarrassment but until then I would love to know if anyone knows of a place. I am being serious and would just love the confidence of being able to be in public without having to go home for a change. Thank you for any help and for serious responses! I understand if no places exist where I can get a diaper change but I thought it wouldn't hurt just to ask.