That is not normal. Even with location on, bluetooth on, and facebook the phone should last longer. I have a friend with an 8+ and I have an X. He is always telling me how his battery last two full days and I can almost make two days. He leaves location on and bluetooth on. He is on facebook, instagram, etc way more than me. He loves the long battery life. We also live in a low cellular signal area which causes the phone to constantly search and still his battery lasts.
You can do all the energy saving steps - turn location and bluetooth off, remove Facebook etc, but in my opinion, you should not have to do any of that. That is a new phone - there is an issue with the battery. 3 hours is not acceptable and I would be contacting Apple.
Lisa