I am very happy to see you all are so willing to help me! Its very reassuring.
Whatever gave you the idea we'd want to help?
Just kidding.
Ok, let's start small. You said you're doing water changes and watching salinity. What do you keep your salinity at? How often do you do water changes? I personally recommend 1.025-1.026 for salinity and 10% weekly water changes (unless you don't use a skimmer...in that case I'd do 15% weekly.)
What is your water source? Do you use dechlorinated tap water, RO/DI water, etc?
What are you testing other than salinity? Anything? Ammonia, nitrite, nitrate, pH, alkalinity, calcium, magnesium, phosphates, etc?
We'll try not to overwhelm you...and stick with the basics for a while. It's easy to get overwhelmed, especially when you weren't planning to be the full caretaker of a tank.
Nikki