Issues with pressing buttons

I am new to Unreal Engine. I am currently trying to make it so I can press a button, and it takes me to a new level. I have done this but when I press the button it first becomes small, but does not take me to a new level. On the second press, when it is small, it takes me there. I need help on why this happens.
(before I press host game)

(after I press host game)

(Second press)
(I also dont know why that menu comes up as an overlay, I want the previous level [main menu] to disappear])

(Blueprints for Main Menu)

Help is much appreciated.