Timeline Scroll - Please Help

[#1]

Hello, whenever I try to drag my playhead in my timeline it will not follow my mouse but instead goes where my mouse clicks (on timeline only) Also when I try to drag volume up from the audio track in the timeline it no longer allows me to do so. As well as when I try to scale an image by dragging the scale in fx motion left or right, it no longer allows me to do so. please help, it was working this morning, I must have clicked something?