You are 26 and healthy. Everyday people are exposed to toxins, air borne illnesses, common viruses, the flu. The list could go on and on. Rarely do people fall ill quickly, especially those without compromised immune systems. Unless you have reason to believe you are immunocompromised, you statistically are going to be just fine. Seriously, there are worse things in a fast food hamburger. Going forward practice hand washing. No need to stress though. I wish you all the best!
Unless your immune system is compromised your chances of getting e coli in this instance are next to nil.
Seriously doubt you will contract e coli if you have a normal immune system.