Correct Assessment?

I have an employer and I recently took additional work as a freelancer. I have logged in my first two non-taxed invoices through the "Add missing income from another source" and picking "Non-Coded Income". Is this correct? Also, will I need to file an additional self assessment form? How would I go about claim tax back on my freelance work, does that come from the self assessment form itself?

Hi 
 Freelance work is self employment income and you need to complete a Self Assessment tax return.
Please see help here: 
Set up as a sole trader: step by step
My first Self Assessment tax return.