Great news Sam!
Kudos on your attitude. You handled that really well. Our doctors aren't always the best at bedside manner. We need them to be competent, support and touchy-feely good vibes can come from elsewhere. He does get points for saying he didn't know, not all will admit that.
Give yourself some time on the lexapro. Benefit from antidepressants is not immediate and some positive brain changes that occur from the neurotransmitter boost take time to set in. Side effects can be onerous in the beginning but lessen as you acclimate. If this doesn't work out there are other options.
Keep up the good work,