I'm still a novice (haven't yet published my first novel. Want to get a decent chunk done before I start posting) however...
step 1: Eat some ice cream or froyo or whatever cold treat you like. I'm personally partial to frozen fruit mash.
Step 2: Take a step back and do a hobby. I learned to throw playing cards. This gives your brain something else to focus on with solid, tangible results.
Step 3: free write. This means don't worry about editing. Don't worry about flow. Don't worry about thinking how when or if you'll publish it. Open a new word document and just type - Or, preferably, use pen and paper. This forces your brain to slow down to your hands more than typing does. the purpose of this is to simply put words on paper. This is also MUCH more useful for writer's block, but it helps keep the habit of daily writing that you've already developed, but without the structure and lock-in that can cause burnout. If you happen to come up with some cool new idea for your novel, write it separately, then keep going.
Seriously, try this for a week or so. That's what helps me and a lot of my friends in my local writer's group.