It probably has more to do with your clothing wadding up in your crotch than the pressure, which is not any greater there than anywhere else.
Since I started squatting/deadlifting I have noticed I occasionally get small purple bruises in my adductor/groin area. I am guessing it has something to do with high pressure exerted on this area when lifting, but not really sure.
It is painless and I only notice it when taking a dump, probably because all my naked time in front of the mirror is spent flexing more noticeable body areas then my groin.
Is this brusing standard and no big deal or indicative something is wrong?
It probably has more to do with your clothing wadding up in your crotch than the pressure, which is not any greater there than anywhere else.
I sometimes get brusing on the outside of my thighs after deadlifting, or less occasionally on my triceps. I've always assumed it was related to microtears in the muscle.
Capillary breakage and bruises are two different things, with quite different appearances. If blood is visible under the skin, it has to come from a torn muscle in sufficient volume that pooling occurs, or it originated in the skin itself. A bruise is a hematoma of varying size, and broken capillaries have a "stippled" appearance.
FYI, if you are doing Starting Strength, any time spent looking at yourself in the mirror (naked or otherwise) should be to judge how your squat form is. This is because flexing in the mirror is very gay. You have been informed. Please tell everyone you know I have said this.