Could my compression vest too tight if my penis and scrotum are completely turned purple?

This is a completely normal effect from swelling after abdominal and flank liposuction, especially if no drains were put in or if the port-sites were closed with sutures.  Even if left open, the fluid that is used during surgery drains in the direction of gravity (downward) and accumulates inside the scrotum and penis.  If the compression feels too tight, you can loosen it a bit.  Numbness is normal for many days post surgery.  Contact your surgeon if you feel something is wrong, but the descriptions you are giving suggest normal post-operative expected results.  I wish you the best of luck, Dr. Emer.

Bruising and swelling can be normal after liposuction, but if I woke up with a purple penis and scrotum, I would call my surgeon and not waste time posting a question online. Only your surgeon can properly address your concerns and make sure this is nothing serious. 

If you're still able to breathe properly and you don't feel pain while wearing the garment, it should be fine. Swelling and bruising of the genitals is very common following liposuction of the chest and stomach.You should probably speak with your surgeon about this, however. If there is an excessive amount of fluid in your scrotum your surgeon may be able to resolve this issue.