You do not say what version of TT you used for your original return. If you only used Deluxe you will need to upgrade to Premier for the form you mentioned.
https://ttlc.intuit.com/community/forms/help/where-is-form-8949/00/25799
As for whether it is too difficult---only you can decide if it is too difficult to amend your own return or whether you want to take it to a professional. It is possible to amend using TT software.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
