Re: How can you tell if it's working?
I think it should show in your actions. You may start going out more, perhaps become more sociable, feel more confident etc. But others may notice the change in you a lot more. They may comment on how you've changed, that you look better, more active and energetic.
But you shouldn't rely on the medication to "cure" you. If you've had a lifetime of feeling the way you do then it's going to also take some effort from yourself through other therapies and self-help.
Medication though is a step in the right direction and I hope it works for you.
__________________
KK
Never Surrender, Comrade