Phases of insomnia?

Hi, I've been consuming 1/2cup of single-strain Reuteri yogurt every day for the past 2 months (1st thing in the morning) and have had three phases of bad insomnia. I'll wake up at the exact same times during the night (1:00, 2:30, 3:30, 6, 7:30, etc.) and have horrible sleep quality several nights in a row, and then skip yogurt for a couple days and it resolves. Is this normal? I don't have any other side effects (including good ones, I believe) from the yogurt.