It is possible and one thing my Pdoc said to me was that antidepressants shouldn't make you feel worse. That was one of many indicators to him that I was in fact bipolar. I'm bipolar type II and I've experienced what you have talked about.

Just write or print out what you described to us and take it to your psychiatrist. Your symptoms while on Lexapro are a little worrisome and you may want to call your doc before your next appointment especially if it is a long way off or you keep feeling really bad.

My Pdoc specialized in depression and bipolar and he recommended the book "Why an I still depressed?" Which talks alot about bipolar type II and soft bipolar. This may be a helpfull book for you and answer some questions about your symptoms and there is a section about talking to your doctor that may also benifit you.