I started taking Lexapro 2 days ago and am not liking the side effects. I am wondering how long it will take for my body to adjust. Both mornings after taking it the night before I have woke up with a terrible headache and stiff neck, clenched jaw (which happens all day) and today I have the chills too. If I know these things will be short lived then I can just suffer through it for a few days, but if it is going to be long term then it isn't worth it. Anybody experience similar side effects?