i had that when i started reading manga and came up with a story that i wanted to draw to this day i am terrible and have recently decided that i will stop chasing this dream it was really hard to draw over and over and get no results so i gave up  however i think that having multiple things to do is a good thing you get to choose what to do and if you are not in the mood you can do other projects i usually get a lot done when just starting to work but then there is a break because i just am not interested anymore and then i realise that 3d modeling a phone stand will make a worse stand then a one i will buy so i wrap the project  if it is actually a good idea then i am okay with continuing a few weeks later i became really stressed when i force myself to do things then i get bored and not like the project  i dont think you should be pushing yourself to finish unless you actually want to because chances are you will do it later in a better mood if it has been too long ago maybe then try revisiting it