Could Creatine And Lexapro Taken Together Cause Side Effects?

I am a 72 year old female who recently read that taking Creatine and Lexapro together can make you feel more energetic and brighter. I already take 20 mg's of Lexapro daily and was beginning t o think I was going to have to get my doctor to up the dosage.I have now been taking the above combination of pills for 2 weeks. (Didn't consult the Dr. about it.) I find that I am having a great deal of trouble sleeping at night, which is unusual for me. Could this be a side effect of taking the two things together?