It's okay. It's perfectly normal. You don't have to know everything. No one can possibly know everything. We all have our areas of expertise. But we have to know our limitations. It's okay to ask for help from someone more educated on a particular subject. Don't be embarrassed.
My parents had a friend named Jack. Jack was the nicest, sweetest, most generous guy in the world. He would do anything for you. Anything. Without question or reservation. Jack was also an idiot, but he knew his limitations. He knew he was not smart and he didn't pretend otherwise. He knew that any situation that required rational or logical thinking was beyond his capabilities. And Jack was the happiest, most stress-free guy I ever met.
Several jobs ago, I had a boss who was rich. Very rich. Rich beyond words. He had more money than you or I would see in a hundred lifetimes. And he believed that because he was rich, he must be smart. And he was smart about certain things. Not about every thing, though. He was business-savvy alright — I'll give him that — but that's where his expertise ended. He was not creative. He was not artistic. He was not an actor and he was not a computer expert. However, he fancied himself all of these and, since he was rich, he must be smart and since he was smart, he was good at everything. He peppered his speech with buzzwords and phrases that he picked up here and there. He didn't exactly know their meanings, but he would inject these words into conversation. When he spoke with experts on a particular topic, he would use words roughly related to the subject at hand. He would use them incorrectly, but it didn't matter. His inaccuracies and lack of knowledge on the subject were spotted immediately, but in his mind, he knew what he was talking about and that was most important.
The moral of this tale is "be yourself." It's okay to consult another, more experienced authority. It's okay to say "I don't know."
And if you're gonna bullshit, you better be really, really good. I mean really good.