I might be able to give some logic to your dilemma. Tho I can't talk on serotonin issues etc but your personal place right now.
I was introduced to dmt by a friend of mine, and I had a few experiences that were very meaningful to me, but my friend had a very bad one, and gave his dmt to someone else so I was and have been left in the dark for some time now. Though one experience I had I got told "don't worry you'll be back".
Now if the dmt experience is a real thing as in another place etc.. then I've nothing really to worry about, as I was told I'll be back, be it when I die, or when I somehow get more dmt.
And if it's not "real" and it's just the brain going a bit nuts on a drug... Then I've literally not lost anything, infact I am perhaps protected from its possible delusions.
So either way.. I'll let it be.
I do seriously want to try it again, I really feel I need it. But it's not to be right now.
The devil wants to climax now. The devil wants all the plesure and none of the work. The road to hell is paved with good intentions.. without work... it doesn't work.
The devils greatest lie is we don't have enough time..
I personally would and am trying to be patient. If you're doing these things for plesure and entertainment, I'm my opinion.. thats a very bad idea. If you're not, then I'm sure you'll be fine for a good amount of time. No rush.
I see you have mentioned about being ok with this, and wanting other perspectives. Unfortunately I'm not educated enough to give any real chemical advice on why this happened