Maybe you could focus on getting your more important things done in the morning, and schedule more rewarding, liesurely, and or optional activities in the afternoon.
It is extremely common for people to loose time to social media. Most of us have some experience loosing more time than intended to this kind of activity. It's also okay to allow for time to do non-productive things. Down time is important. But if you feel like it's getting in the way, restricting your access, or deleting apps that are too distracting is also fine.
But just FYI, personally I am so exhausted by my day job, that unless there is something vital to do, I pretty much vegetable once I'm home. I have anxiety and depression (both treated), and to be healthy I need time where there's nothing I have to be doing. Do I wish I spent that time working on my comic? Yes. Do I force it? No.
I feel like it comes down to self control and motivation. I have no idea if you're a student or work or what, but for example.. if at your job you spend an hour on facebook instead of your assigned activity, you will probably get written up, if not fired. If you play on the internet instead of doing your homework, you hurt your grade. You are responsible for making sure you do the things that you think are important to do. But that should include breaks.
This is a package of advice most comic creators will give newbies- create a buffer. You almost always want to be several pages ahead of what you are posting online, because RL includes unexpected interruptions. My ideal schedule was posting one page of the comic per week online, with 4 pages already finished. I would take a month long break from posting pages between chapters, and a week or more midchapter, specifically to give myself time to work on the buffer pages.
One page a week isn't the only possible schedule, its about figuring our what makes sense with your life. You've talked before now about speed being a problem, so forcing yourself into a schedule you can't actually keep up with seems like it would cause more stress, which can feed into the problem. But there are people who work best with the stress of a deadline, so this isn't meant as "one size fits all" advice. Just food for thought stuff.