What does a negative net income mean if you are self-employed?

If you had more expenses than income, you will have a negative amount on your Schedule C, Line 31 and on your Schedule 1 Line 12.

is s this a bad thing?

If you have negative net income and are self-employed, then negative self-employment income may generate a net operating loss on your return if it exceeds your earned income. 

If you have a "true" net operating loss (verified by Form 1045 Sch A), then you may able to carry it back or foreward against other years business income.

You have to ask yourself if you are operating this business in a "businesslike manner" trying to make a profit.