What is happening to my bike?

Hey I’m new here and new to riding and worried I might have messed up my bike or bought a bad one or just be overreacting. I had to drive it about 150 miles after I bought it and it was fine. I drove it today and it was fine. Later tonight I was driving it to the store and It felt different.When I’m getting up to speed and shifting it’s riding normal but somewhere around 40-50 it starts to feel shaky? If I have just the clutch pulled it feels smooth but when I’m just on the throttle it feels like it’s shaking/ giving quick thrusts of power. It’s hard to explain in words but it’s a rocky, shaky very fast bursting feeling.Could it be me being in the wrong gear? Or a rotor? Again it feels smooth in early speeds and with the clutch pulled it’s smooth but when I am getting higher speeds something feels off. via /r/motorcycles https://www.reddit.com/r/motorcycles/comments/d41pbf/what_is_happening_to_my_bike/?utm_source=ifttt