What's the best way to ask my pcp for a referral! she doesn't have a clue what's wrong with me. i don't want to come off rude!

Just ask: You can just ask if they think that a specialist might be beneficial to get another opinion.

Ask: Most primary care doctors including myself are quite familiar with the referral process and literally make them 2-3x per day. If you indeed have lupus you will likely need to talk to a rheumatologist at some point in the future anyway. If the diagnosis in not clear there may be other connective tissue disorders that need to be ruled out. Just ask:).