I see my counselor once a week on Thursday afternoons

I went to the doctor on Wednesday about my being constantly lethargic. She gave me a three week sample of Lexapro, though I'm apprehensive about using it. My dad is a doctor and he said it would be fine if I wanted to use it. I'm still debating it though. My counselor said it's a personal choice to make. The reason I am apprehensive is because people have told me it can make you an insomniac. For example, if you go to bed at midnight, you wake up at 4 AM and can't get back to sleep. You go to bed at 5 PM and wake up at 8 AM the next morning, etc...

Do they sell the velerian root capsules at normal pharmacies?

Also, I seemed to be sleeping well before the cold and I know colds can linger because I get at least 4 of them a year. I honestly don't know...