1. Before realizing that the itching on my lip was a small cold sore, I used the same towel to wipe my face and then my genitals after showering.
You already have hsv1, which means you have antibodies that will protect you from getting it in another place on your body. Autoinoculation, which is what this is called, almost always happens when someone has a brand new infection.
If you don't have hsv2 already, hsv1 won't protect you from getting that from a partner, but you won't infect yourself again now with hsv1.
2. I frequently touch my mouth while thinking or as a gesture, and then go to the toilet and forget to wash my hands before touching my genitals (usually an hour or so has passed)
See above. You don't need to wash your hands before going to the bathroom. Herpes dies pretty quickly once air hits it, and you have antibodies.
A note though - if you are touching your mouth a lot, that's a great way to get colds, flus, etc. Might be a good idea to try to break that habit.
You aren't a walking biohazard. You're really okay. :)