Fund a active wheelchair

I've been disabled since I was 12 years old and have struggled with mobility, energy levels and pain since then, I'm now nearly 23 and have had little or no help from doctors. This has lead to my adult life being very isolated and depressing. I can't just pop to the shops or go out with my siblings without being in agony, most of the time I just don't bother and stay in my flat. It's a very isolated existence not being able to walk or stand for longer than a few minutes. I'm only 22, I should be able to do these things like other young people. It's taken me a while to decide that I really need to get a wheelchair to live a more fulfilling and less pain filled life. I can't work because of my health so scraping up the money for a wheelchair that is suited to me would take years and years, I'm really hoping someone can help.