Don't be so hard on yourself! I'm a firm believer that all experience is valuable in and of itself. The things that may have gone wrong this time around will be easier to do the next time. They key is to not give up. Most game devs create a game for a jam that doesn't end up great and they decide its not for them, but if they kept going for another jam or two, they'd really blow themselves away with what they're able to create.
You're in a great spot to make something great the next time around, regardless of how you feel about the current jam. Don't give up, stay positive and keep going! <3