[KJohn]

Welcome!
How are you warming them? and no, glass changes colors with heat, depends on the color. If they stay darker, like the turquoise or some other reduction/striking color, it's ok as it should work out when melted. From the looks of that ivory and some sooting, you are working a little too close and long near the torch head, try to work further out and be comfortable letting the bead cool a little when adding decorations. Melting the decorations or additional layers on doesn't mean remelting the whole bead, only the outer layers as much as possible, and you will find keeping those pretty colors and shapes much easier. P.S. Don't twirl too fast. I still do that sometimes when I'm in a hurry, slow down and it really helps.
Looks really good otherwise. Just keep practicing.
I was like you when starting, I read everything I could find (youtube wasn't a big thing for lampwork videos back then like now) for years. I've never had a class. The archives here are AMAZING.
Don't be afraid to post in the gallery and chat, we are always happy to help