calendar times when creating new event

i am disabled and use my calendar a great deal. it's great for helping keep track of when i did something. except for the fact that it won't create events and display real time. even if it's like 4:59, it will display 5:00, at 5:00 exactly, it will display 6:00. i hate having to input the time myself to make it exact. like i have to manually type in 2:30 or 3:18 myself. why does it NOT display an event in real time?! why do i have to do it myself, every....single....time!! help, please!