See if it works better for you. You can still file the Schedule C with deductions for that business, and use the standard deduction Schedule A for other items (medical stuff, charitable contributions, etc.). You also may need to obtain a Seller's Permit at least for sales in your home state and pay Sales Tax to that place (Texas?). If you don't already have one.
In other words, I am licensed to Sell in California and required to report my transactions and pay our state for taxes collected from in-state sales. Sales Tax paid is another deduction on Schedule C. Once in Las Vegas, I am not allowed to sell things. You have to meet me in my hotel room, I slip a chip under the pillow and slide it over to you, you look and say "Wowweee! Must have been left by The Chip Fairy" - then you put a dollar or much more under said pillow and slide it back to me. And I say, "Yesh, dat paysh fer me losht baby toot!"
Final note: I am not a tax professional, this is advice as I know it, but you may also wish to consult with a tax preparer or CPA for the best advice, particularly as to Texas law.