If you have the developer options enabled it sounds like you have the animation scales turned off. Turning them off gives the appearance that your phone is super fast when transitioning between apps, one screen to another, etc
Thank you for reaching out. Do you experience these symptoms if you test your device in safe mode? If your phone is misbehaving, it's possible that a third-party app is causing the issue. To figure out what app is acting funny, you can use the Safe Mode feature. In Safe Mode, your phone won't run any third-party apps. This allows you to easily identity and remove the app that may be causing the problem.