Jailbreak won't delete anything from you iPhone, but since you updated to 7.0.6 directly OTA and not through iTunes, there is a good chance, that jailbreak could fail. It doesn't happen always, but just saying, to be aware of that possibility. Anyhow, if it fails, than you wont have any other option, but to upgrade to 7.1.1. Unfortunately, so far, there is no jailbreak for 7.1.1.