I just found out a person with tuberculosis was in contact with me at work.  how risky was that interaction? Should I get tested?

Yes. If your colleague has active pulmonary tuberculosis, the health department will do the testing. If he/she has latent tb, you are not at risk and need not be tested. The risk of catching TB depends on factors related to how close a contact you had, for how long, and how advanced the case was when exposed. It is transmitted by airborne droplets.
Screen. The transmission is by airborne droplets. The office workers should all be tested if there is a case of active TB in the office.
Yes. You should get tested and evaluated by your doctor. If your initial skin test is negative you'll need repeat testing in 8-10 weeks.