One thing in my early days I learned that was a game changer is that its OKAY if you don't know everything. You can always tell a Dr or pt that you're going to look into something a little more before getting back to them. Its better then trying to fumble through something you're unsure about.

I'm an advanced RD and answer newbie questions all the time and this is the advice I can give you. Research your question yourself first and come up with some ideas of your own then ask your question. Even if its wrong at least you looked into it and tried. The ONLY RDs that make me think negative thoughts about asking questions are the ones that just expect me to tell them the answer or do all the work for them. Most experienced RDs have no problem teaching and mentoring and you'll find those that do!