That "fair salary" has to be reported to you on a W-2 and you should be receiving paychecks with taxes withheld, paid to you by the S-Corp. Are you? I expect that's not the case, I expect you reported the full $150K on Schedule C so, ergo, it's all considered self employment income.
And yes, you need to first prepare Form 1120S, which will create a Schedule K-1, which you will enter in your own Form 1040.
If you are the sole employee of the Sub-S corp the IRS's default position is that "you" should be receiving a salary of $100K. You might want to go to a local tax expert to get set up properly.
