How are you paid? Are you a dance teacher employed by someone else and you receive a W-2? Or are you in business for yourself?
If you were a W-2 employee, $14k is far too much. You would owe 7.65% in FICA/Medicare on the entire $43k, or about $3,290. You would pay around 13% in federal on about $33k (the first $10,400 is exempt), or about $4,300. If you pay state income tax, I'll go with about 5% (could be more, less or none) for $1,650.
That's a total of close to $9k. If you are not counting the FICA/Medicare you paid in that $14k, then subtract that $3,290. It looks like something is off by quite a bit.
Even if you were self-employed and had to pay the employer's share of FICA/Medicare as well as the employee's, your total bill would still be under $14k.
Edit: Just saw your comment in the form of an answer and I'm a bit confused. On one hand, you say you're paying self-employment tax and on the other, you say you have a co-worker. It can't be both. If they are also self-employed but doing the same thing you do, then they are not a co-worker, they are a colleague. Co-worker implies that you are employees and suggests to me that your employer is illegally classifying an employee (you) as an independent contractor, and not withholding your income tax and FICA/Medicare, and not paying their share of FICA/Medicare, and sticking you with all of it. So, which is it?
Because it's important. If you are truly self-employed, $14k isn't that far off, because self-employment tax WILL be part of that number. If you are truly self-employed and in California, the numbers would look something like this, assuming that the $43k is your net business income (the $10,400 exempt number already taken out, plus all business deductions, which means your gross income was much higher than $43k).
Your federal on the $43k is around 15% (you are at 10% on the initial part, 25% on anything over $37,950 and 15% on the rest), or $6,450.
Your self-employment tax is about $6,100.
California state tax is about $1,250.
Total is $13,800