Over the last 12 hours I've received a large number of responses, and I'd like to thank you all for the detailed and helpful responses.
Clearly, I've been doing this incorrectly, however, I do have a number of experiments already done that hopefully I can salvage something out of. Now, at high concentrations of substrate I do get a hyperbolic curve, suggesting some sort of saturation occurring, and a half max at ~ 0.5-1mM. Now, although I haven't done the kinetics experiment properly, is there anything I can interpret from this data? As a reminder, my incorrectly done assay has been fixed concentration enzyme (~10uM) + varying substrate, 90 minute reaction, and a quench and detect with UV post. Again, thank you all for helping out a hapless grad student.
