Afraid not, man. If you feel like you're gonna go back to a peice of work and improve it at some later point, you need to save it as a .psd file. You won't be able to upload it anywhere as an image, mind, but it's always good to keep back ups. Also, for the actual image file, I suggest you save it as .png rather than .jpg. Jpeg files tend to lose quality, while .png keeps it.