Should I go to grad school if the career I want will only make 50k?

You can get more than one master's degree. And certifications. And a PhD or two.

50K for starting? What is the career?

Will the employer pay for your higher education? Can you get hired without the advanced degree?

50,000 is not a bad salary, but the real issue is not the money, it is the job you are happy about. You need to find and enjoy your work.