I have done daycare, crocheting, knitting and selling it at local shops that do cosignment selling, sold a couple pieces of artwork, Volunteer work like cooking for community events, Library volunteer work ( local librarys need people who are willing to sit in a room cleaning and repairing books, logging in books on computer card catalogues and so on.) hang in there. Call around your community and you will find many opportunities that don't require you to be on you feet or sitting for hours at a time.