You should look into a new career if you are afraid to learn new languages. However, something to keep in mind is that learning a new language is generally not

You should look into a new career if you are afraid to learn new languages. However, something to keep in mind is that learning a new language is generally not very difficult if you know a similar language in terms of semantics (i.e. NOT syntax). For instance, since you know Go, learning Java should be pretty easy since they have very similar semantics since they are both garbage collected languages used primarily for writing server side programs.