***********NOT A DOCTOR**************
For me, Lexapro kinda came in through the back door. Research suggests giving SSRI's at least 1 month to build in the system, but 1-2 months is ideal. It took 20mg for me to notice changes, but everyone is different. You're doing it pretty slow which is good, but you'll have to give it some time. At the time you reach your prescribed dose, you really should give it 1-2 months to notice changes. So, if you're increasing drops slowly, you can't really start counting the time you've been on the medication until you reach the prescribed dose. I say this only with the intent of fully giving the medication a chance and not stopping too soon.