For the longest time I've had an issue with anxiety that was left unaddressed until I finally spoke to a specialist about it and was diagnosed. About 2 weeks ago I was put on a mild antidepressant mainly to help me sleep as I also have a physiological condition believed to be caused by stress and anxiety that makes it particularly difficult to sleep at night. 

First night x1 dose of 10mg of the TCA and I didn't really feel anything. 2 night x2 dose 10mg and it knocked me out. However, I woke up late, feeling absolutely rubbish - unmotivated, tired, and malaise. Since that experience I dropped the meds and just went without it at the cost of some sleep and ofc the general anxiety (hard lockdown in VIC, AUS isn't helping either sadly). Anyway, is this common? Is this one of those things where  "it may get worse before it gets better?" Or is this the medication working as intended? It does make me feel less anxious in that it puts me to sleep but it also makes me feel extremely tired and unmotivated the following day.