Don't inhale solder and flux fumes ... you end up coughing up a lung or two, and if you do inhale enough of it (i've got some stupid friends) then your poop may turn black for a day or two.
In other words, make sure you have some way of moving the fumes out of your workspace, preferably having a wide open area, and or a fume extractor (Weller makes a great one).
Not sure what flux is that. I use pure rosin (colophony, Greek pitch - it's just solid pine sap) exclusively, never used anything else, and it's not nearly as bad. It's no different from incense in any way. One reason to stick to colophony is that I kind of like the smell. Incense-smelling clothes and hair were a staple of my teen years. :)
With proper technique, rosin is highly effective as flux.
Once I did a trial with aspirin instead, out of curiosity, but that stuff is devil's brainchild. It's very effective, it allows you to solder stuff on oxidized surfaces without problems, but the fumes will burn your nose, throat and windpipe - and maybe lungs too if you breathe deeply, which is pretty hard because you start coughing immediately. It's acid smoke, very corrosive. I tried it, then refused to use it again.
I've found that the newer no-clean and water-based fluxes give off some fairly nasty fumes. Rosin flux unless it's a very heavily activated type doesn't really bother me, although if I had a job that exposed me to it regularly I might start to worry about long term issues.
In other words, make sure you have some way of moving the fumes out of your workspace, preferably having a wide open area, and or a fume extractor (Weller makes a great one).