It's inevitable that you will have good days and bad days. It's when the bad days stretch on for weeks and months that you really need to start asking hard questions.
During my first tilt at transition I was on HRT for two years, the last six months of which were a misery. I realise now that misery was a combination of things - fear, reaction to some of the HRT (Androcur is known to cause depression, as is cycling injections of Provera Depot), poor social skills and isolation, various other unresolved emotional issues and poor coping skills, etc, etc. Maybe I could have made it though but I chose not to and stopped the HRT. Bottom line is I just wasn't ready to transition then.
I then tried to tell myself for the next twenty years that I wasn't trans, that I had been insane or something. It wasn't until things got bad enough that I had to face the truth of the matter, and it wasn't until I could accept that it wouldn't be an easy path and accept myself that I was able to take HRT back up again. And it's working pretty good this time!
Some people try several times before they find the right circumstances that work for them.
The thing to remember is that HRT is not a panacea, if you have other issues to deal with it probably won't solve them, it will feminise your to a degree but often you need to put in a lot of extra effort, I know I did. And it takes time.
