First Time Filing Taxes
When you obtained the EIN for your LLC, you had to tell the IRS how you wanted the LLC to be taxed. LLC's are what is known as "check the box" entities for federal tax purposes. If you elected to be taxed as a sole proprietor also known as a disregarded entity, then you do in fact file the LLC revenue and expense on Schedule C with your personal tax return. Since SSDI is typically impacted by your 1040 income numbers and the LLC's income or loss is included in those numbers, you SSDI is likely going to be impacted by the LLC's profit or loss results. More likely to be impacted by profits than by losses, but you really need to discuss your specific situation with a tax professional and also possibly a financial planner.
If you elected some other form of entity, then the answer might be different, plus I don't know all the specifics of your situation so all I can give you is general guidance, another reason you really should discuss your circumstances with some professionals.