When you have saved your computation (again, good job!), there are certain steps you can take to test your computation in order to see if it works as you would like.
Step 1: Check your questions
Check the names of your questions (the fieldname) and the names of the options or values of the question. See if they are the same as you use in your computation. If an option is an 'number/integer' make sure the type is also on 'number'. Check capital letters, underscores and dots.
Step 2: Check the data output
Fill out your questions in your document and press 'save'. Go to the computations tab, en scroll down. There you will find two windows, in the upper part, the 'data object' you will find the data that comes out of your document. Is it as you would expect?
Step 3: Check the computations output
What comes out of the computations 'object'? Does it give an error? If not, chances are your computation is correct. Well done!