First time being in an applied math lab - what are some tips to overcome shyness?
Since you are asking about viscosity, there must be some kind of fluid dynamics in your lab. Schaum's Outline of Fluid Dynamics is quite useful as it has worked out problems.

If you have actively avoided all social situations, never asked a question in class, or even had lunch with a fellow student, then perhaps you need to investigate resources at your institution to help overcome your extreme shyness. This will be a significant problem for you in the future - regardless of whether you stay in academia - if you don't take care of it now. Don't wait until you get older.