I bought this tree about 6 months ago, its about 3 years old ...
I have started fertilizing it for about 2 months now, after the last
time it looked considerably worse the next day. I had been told I could
Miracle grow at about half the dosage listed on the box. I really don't
know what to do now to help it get better. The leaves on the
underneath of it have always been brown (I was told this was normal)
but now the leaves on the top have started to turn as well since the
last fertilizing.

I have been watering it regularly since I got it. I spritz the leaves
daily and don't allow the base to dry out at all. I would greatly
appreciate any advice on what to do here to care for it.