Well they say that it hurts and that it comes in a blister form. So chances are that it isn't a herpe. I would get a test done just to be safe and to give you that peace of mind.
It wasnt a blister at all, it never bothered me or pained me before, the only way I know its there is when i feel it or look down.
Does the patch look like a blister at first? If you gf is having pains after or during sex it could be something else but she should have a pap done anyway and you both should have a blood test done to be sure. When you get the blister on your penis you should go to the doc and get it cultured. That will be the best way to find out if it is hsv and it will tell you if it is 1 or 2. I am not an expert thats why I am recomending you go to one. Good Luck!!!