Collect W2 and side business

Hello!

 

I am a full-time employee (receive W2) located in South Carolina and just started my E-commerce business two months ago as a Sole Proprietorship. The revenue is about $8,500 so far and is expected to grow. I am collecting all the expenses (receipts or bank statements), profit, and net income by myself for the record.

 

When the tax season comes, I am thinking of filing my regular 1040 form with Schedule C. I will claim the home office and everything that comes with this E-commerce business under Schedule C and then file my full-time job on the 1040 form as usual.

 

Questions:

1. Based on the above information, do I miss anything? 

2. Do I have to file the e-commerce business tax quarterly? What's the benefit of filing it quarterly?

2. Am I considered the self-employment? Should I file the Schedule SE?

3.  What is a Quarterly sales tax and Quarterly Self-employment taxes? Do I need it?

 

Thanks a lot for your time! I appreciate any suggestions and information.