Did I waste emergency services' time?

I'm really not sure if I did the right thing here, but also not sure what I should have done instead. I was walking along a street and came across an elderly man who was sitting on the ground in front of his house, he told me he had fallen and couldn't get up and asked for help standing up. I tried to help him up bit he was a completely dead weight and couldn't support his own legs so I had to leave him seated. He seemed confused and couldn't tell me if there was anyone I could call to help him so I dialled 999 and asked for an ambulance. They took about 15 minutes to arrive and by the tine they got there the man had managed to stand up and was keeping himself upright by holding my shoulder. When the paramedics came to us they asked me if we really needed an ambulance, to which my answer was that I didn't know. Did I waste their time? Is there another service I should have called?