Assuming your tests 4 months ago were blood tests, you can pretty much rule out herpes. The only exception, which seems unlikely, is if you were exposed to HSV-1 within the 3 months before the blood test, i.e. too soon for the test to become positive. A more likely diagnosis is angular cheilitis, an inflammatory lesion at the corner of the mouth. It can be due to a variety of underlying causes, including malnutrition, and also including HIV. So if not tested recently for HIV, it would be a good idea. But in most cases, no predisposing cause can be found. And I'm not at all sure that's what you have--just an educated guess. In any case, don't just keep guessing, and don't try to figure it out by online description; see a health care provider.
In the off chance it is herpes, you really don't need to worry about transmission by hand-to-hand contact. Kissing or oral sex are the only likely routes of tranmission.
Good luck-- HHH, MD