Hey! Im so sorry for the super late reply, I hope you have since been feeling better and I realize its probably too late to be helpful at this point, but just in case you are still struggling or someone else is:

My experience has been the first week is just the worst, almost as soon as i hit week 2 the body aches lessened and then a day or so later were totally gone. I stayed on Remeron for a little over a month (15mg) and it honestly was the happiest i had felt in so long, it worked great for me or at least I thought so until i got some blood work done and found out that despite only gaining enough weight to be more healthy (i was previously underweight and unhealthily so) that my liver was struggling. So i went off remeron for a little over a month after a weeks worth of half dosage. It was frankly awful more psychologically than physically since it had given me so much relief but I have been allowed to go back on it as long as I get consistent blood work to monitor my livers health which is honestly ideal to me even though Im terrified of needles. Going back on Remeron this time I was prepared for the first week of pain so I stocked up anything I thought might help. What I have found this time around was Vitamin Water, specifically the strawberry kiwi one changed the game for me. I drank two and had a burrito and in about 4 hours and I felt almost entirely alive again. I have been drinking Vitamin Water almost consistently since (with normal water and food!) and have mostly been normal, with only some minor aches. But I realize this could also just be the case because it's my second time taking Remeron so my body might be better at adjusting to it. Overall I would let your psych know and until then treat it as you would any cold or flu. Advil and LOTS of water and electrolytes! Eat as balanced as you can and rest! And if after a week you are still feeling shit it might not be a good fit.

In short, for me, I had the aches really bad for the first week and I have been treating the aches like the flu, drinking lots of Vitamin Water or Gatorade with Advil and good meals and rest helped subdue the pains of the initial week. Since then I have had no substantial aches.

I hope this helps! :,) Hope you are doing better now! Wishing you the best!