It's hard to say what this is, but I doubt it's herpes. Oral herpes - or genital herpes, for that matter - doesn't give you hard bumps. It gives you blisters. This could have been a pimple, a staph infection, etc.
If it comes back, get it checked by your doctor.
No, you do not have herpes of he elbow. I would not worry about this. If you have herpes one on your mouth, you won't get it on other parts of your body. Are you thinking of this? https://www.news-medical.net/health/Is-Dermatitis-Herpetiformis-Caused-by-Herpes.aspx This skin issue is not caused by herpes but people get confused by its name. It's more autoimmune related.
Additional information, we have not been sexually active outside of making out