Budget Planning: Sell luxury car for more cashflow or current cashflow is sufficient?

Hi, I recently graduated and started working for a company.

Currently, the car payment is 36% of my net income (this includes insurance for 5 years, 5 years is the term of loan @ 6.85%)

Currently, I save only 20% of the net income, and I am renting an apartment for 11% of net income

I've been reading a lot about investments I am in the disposition to sell my luxury car (which I realized it was a big mistake, of course this depends on my life's goals ==which now include making money work for me, not me working for money, especially now that I can generate cashflow)

So the question is: I am just 23 years old, and that 20% of "savings" is about $418 per month. I think I still can get started in the world of investments with such low amount of money being generated in a per month basis, but I can certainly generate more cashflow if I sell the luxury car for a modest one and generate, perhaps, $400 more, for a total of $818.

I am asking all this because of my current job security and market conditions, which, in my opinion, are favorable for new investors. What do you think?