I get the idea that you have a strong commitment to Duolingo, as many people seem to. If so, choosing another language in that system makes sense. But if you want to continue with Scottish Gaelic, your library has free language learning through Transparent Languages Online, and they offer Scottish Gaelic. It will start at the beginning, but take a different path through the language, enforce what you know, and offer some new situations/vocabulary/etc.

And if you want to practice Spanish at any time let me know; I am always up for that!

K.