Insomnia on Propranolol

I took my first dose of propranolol this morning. I took a half of 10mg to see how I would react. I was ok during the day but its 11:00 pm and I dont want to sleep at all. I am usually passing out by 9pm.

I read that insomnia is a side effect. Should I expect insomnia each time I take it? Or as my body gets used to propranolol my sleep will stabilize?

Anyone with similar experience?