Apple Mouse Control

I have a MacBook Air 13", 2012. I use an Apple Mouse, Bluetooth, it's white with one button. Worked fine and all of a sudden it does weird things while using. Sometimes it will zoom in and out, in and out and then in and stay that way. I will double tap and sometimes it goes back to normal size or maybe not, I may have to double tap several times or use the keypad. I no longer get a drop down menu when right click on a word, example, if I'm reading something on a webpage and want to check a word for definition I would be able to right click the word and select "Apple Look Up" and the sidebar dictionary would come up. I no longer seem to have that option, even on the keypad. Also, if I have a red underlined word indicating a spelling error I no longer get a spelling correction when I click on the word. I'm not sure if this all started when I downloaded Mojave. Does anyone else have this issue? Or is my mouse bad? I've inspected my mouse and cleaned.