
I'm really sorry you're having such a tough time of it, Sheena. Stairs can be scary - and your worst enemy especially if you are off balance or numb.
I don't have any stairs to deal with but I think if I did I might consider sitting down and "bumping" down the stairs until I got to the bottom. Might look silly and take you a little longer to make it down but at least you'd be safe.
I hope things get better for you - and consider letting a doctor look at your side it sounds like you might have a bruised or fractured rib if it's painful to breathe.
Take care.