crowded thread but since I teach at a university (adjunct professor) maybe I have a unique perspective.
people rarely say exactly what they mean. even when someone tries very hard to do so, it's easy to interpret what's said in different ways. so, it's probably worth giving a little grace when thinking about the professors intentions.
for myself, the feedback I give often comes from the perspective of helping the student to learn and grow. it's POSSIBLE you're professor was coming from a culture that puts a higher priority on dress than is typical in your culture. it's also POSSIBLE that he gave that feedback hoping it would give you insight on how to put your best foot forward in cultures that put greater emphasis on norms of dress. possibly.
finally, I know which students in my class aren't really trying. sit in the back, missing homework, skip class, don't participate, never ask for help, etc. i try to reserve my limited time and energy for the other students who are trying. in this case, a disgruntled student might get angry in response to that comment or gone to the department head to complain about him. if you're professor feels the same way I do (I realize that's a big 'if'), he wouldn't have said anything to you and wouldn't have risked that drain on his time and energy if he didn't think you were worth it.
you'll probably need to talk to some people about it before you secure patent protection. whenever this comes up, have people you talk to sign a non disclosure agreement first. talking about your idea outside of an NDA would most likely be considered public disclosure and could limit your ability to get a payment for it.
talk to a patent attorney