Listen- if your working by yourself unpaid especially, you're doing a whole team of people's jobs (pencils, lineart, colouring, shading, backgrounds, lettering ect)
I see a lot of people who feel they don't make enough, but honestly if it's a sustainable way for you to make progress and do what you do, then you don't need to be hard on yourself for taking a while to get things done. There are a variety of factors that go into the speed of completing a comic update (art style complexity, background complexity, time in the day to work on your comic and of course your own personal drawing speed)
There are things you can do to alter, and tricks you can implement-- there's a ton of threads that can help with that as well:
But, at the end of the day you shouldn't be hard on yourself for making a manageable amount for yourself.
I'm saying this as someone who had to cut down on how many pages I made a week because of my schedule and to prevent burn out- at first I felt kind of crap about it , but honestly I can manage my updates a lot better now. Do what works for you, I'd say, but if you want to change and alter things to fit the amount of progress you're going for that's also a perfectly good way of going about it.