First of all, you may already be infected with hsv1, the most common cause of oral herpes. At least 50% of people in your age group are and most do NOT know it because they never get recurrent outbreaks or their outbreaks are very infrequent.
Second, the cuts between your scrotum and thigh are not herpes. Initial herpes symptoms will appear at the site of maximum friction from the encounter that led to transmission. In your case, this would be the head and shaft of your penis.
The virus needs to be vigorously massaged into the skin for transmission to occur. It can not be just laid on the skin. The reason is that most skin, including on the penis, is highly keratinized. Keratin is a strong, fibrous protein that coats the skin and provides a very effective barrier against a primary hsv infection.
Let's assume you are not infected, i.e. you have no preexisting antibodies to HSV1. The odds that you were infected, even from someone with a blister, are low for such a short duration of exposure like you describe. Also, most people with no antibodies to either hsv1 or hsv2 will show obvious symptoms, i.e. blister, lesions and sores within 3-6 days. If you have not experienced any obvious symptoms by now, it is quite unlikely you were infected.