Yes you do have a business. When you are self employed you are your own business.
You need to report all your income even if you don't get a 1099Misc. You use your own records. You are considered self employed and have to fill out a schedule C for business income. Enter it under
Federal Taxes Tab
Wages & Income
Choose Explore on my own (if it comes up)
Then scroll way down to Business Items
Business Income and Expenses - Click the Start or Update button
You use your own name and ssn or business name and EIN if you have one. You should say you use the Cash Accounting Method and all income is at risk. After you put in your income and expenses if your net profit is $400 or more you will pay 15.3% Self Employment tax in addition to your regular income tax. The Schedule SE will be automatically filled out for it.
After it asks if you received any 1099Misc it will ask if you had any income not reported on a 1099Misc. You should be keeping your own records. Just go through the interview and answer the questions. Then you will enter your expenses.