Hello cactus9,
Thanks for reaching out to the Apple Support Communities. We understand that you're not seeing any push notifications from third-party apps which you use on your iPhone since you have upgraded to iOS 15. Good thinking disabling Focus, to ensure that it's not stopping any notifications.
Let's begin by answering your question about the color of the Focus icon, as it's appears in the Control Center. From the screenshot you provided it appears that you have a wallpaper which is red. This is the color that you're seeing for the Focus icon. If you change you wallpaper, you should notice the color of the icon will change as well.
With regard to the notifications not working for third-party apps, begin by checking the notification settings on your iPhone to ensure that there aren't any notification groupings turned on for those apps, that the apps aren't included in a notifications summary, and that the Notification Style is set to the one you desire: Change notification settings on iPhone.
For more information about the settings for a notification summary, check out the, "Schedule a notifications summary," from this article: View and respond to notifications on iPhone.
Let us know if the issue persists. If it does, is it all third-party apps or only certain ones?
All the best.
