I received a 1099-misc for $300 but it cost me over $200 in taxes when applied to my income?

I received a 1099-misc from some videoing I did which only comea out to a little over $300 for the year. Forst off do I even have to file this since it is less than $600?

When I enter this $300 income and apply it my estimated return drops over $200, which equals around 70% in taxes????????  What am I missing here?

thanks