representing state that has 2 transitions to the same next state and how to perform a 0 switch coverage test on it

I am working on a project where I have to test the states of changing motor speeds (LOW - MEDIUM- HIGH) by controlling multiple switches and buttons, the problem is that there are two ways to increase the speed of a motor either by pressing button A or pressing switch B for 30 seconds.The speed is decreased by pressing button C. I have searched for a way to represent that in state machine and decided that I might draw 2 arrows from state LOW to state MEDIUM one for pressing button A and the other is for pressing switch B for 30 seconds. But I never found such a representation where a state has two arrows (transitions) to the same next state. So I made one arrow and put the 2 conditions and with an OR between them. is this correct?

and in the case of 0 switch coverage testing should I consider this speed increase transition as one transition and choose on of the 2 events(button A pressed or switch B pressed for 30 seconds) or should I consider it as 2 transitions and where each EVENT need to be tested in separate test cases?

motor speed state machine