Is there a local quilt shop near you? Or maybe a local church has a quilting group? It looks like you can save the blocks if you can get someone to show you how to lay a new corner block (of the right proportion)in place and sew, then trim only the corner block you have sewn to what is left of the larger part of the block. Your finished blocks may not be the finished size you were expecting and you may have to add another row to get the size quilt you want. Or add another border. I am pretty much a new quilter myself and I make plenty of mistakes. Sometimes I can't believe what I have done. But to make it work you just have to think about it and change it up a little. It may not look like the original plan but might be really cool. Good luck! And don't be afraid to ask around for a local quilter to help you. Someone from the board might even be close by. We come from everywhere to join in here.