I've followed all of the above instructions, and I'm still getting "waiting for activation" for my phone number. All of my texts are going through my email which is very confusing for people like doctors, etc. because they don't recognize my email

I copied this from the end of the related article that you were reading when you posted your question to the community. It states that you should contact Apple Support for help if the number still isn’t activated after 24 hours. I suggest that you contact Apple at this point.

Still not activated after a day? 

It might take up to 24 hours to activate iMessage and FaceTime. If the issue continues after 24 hours, follow these steps:

1. Make sure that your device has the latest version of iOS or iPadOS.
2. If you're using an iPhone, contact your carrier to make sure that you can send and receive SMS messages.
3. Make sure you can send and receive SMS. If a prompt appears stating "Your carrier may charge for SMS messages used to activate FaceTime and iMessage", tap "OK" to allow possible SMS charges.
4. Contact Apple Support.