No, this is where you are confused about "self-employment". Self employment under US law is where you yourself pay all your taxes, social security, etc.
Here is the IRS definition
(An employer) must withhold income taxes, withhold and pay Social Security and Medicare taxes, and pay unemployment tax on wages paid to an employee. You do not generally have to withhold or pay any taxes on payments to independent contractors.
If you are working for a corporation it is a separate entity, it is not part of yourself, but it is like another person. That is the best way I can describe it to you. It is not you.
If you do not declare the income of the business on your personal tax return and the corporation pays their share of all taxes and pays you a salary which you declare and pay income tax on, then you are not self employed. You are an employee.
It doesn't matter that you own the shares of the corporation.
The only disadvantage to this is double taxation. The corporation pays income tax on earnings and you pay taxes on your salary! But that is corp to corp. And the only way for you to get a TN unless you work as a management consultant.
I know this law well. In my 34 years as a business immigration attorney I have done many of these arrangements for TNs.