I've had terrible difficulty getting to sleep due to depression for years, and the work problems and crying in bed when it got really bad. I didn't really appreciate how bad my depression was until those last two problem appeared and started getting worse. Much worse. It was easy to ignore until then, and you get used to feeling bad, but that's when I realized what was happening and started getting quite scared where it was all going.
There's plenty of sites that tell you the symptoms pf depression, have a lot because you may well have more of them.
I think you need to look into this seriously and do something about it.