I made sugar wash and let it ferment for a week. After that I distilled it but forgot to get rid of the heads. I let it go until it was enough to fill a cup and emptied my pot (I didn’t use all my liquid) I tried to light it on fire but it won’t burn. is it safe to drink or should I be worried about methanol poisoning
If you are using a simple pot still, you may not get high enough proof to burn on your first run. Without knowing actual volumes and ABVs here it is hard to say what is the case here.
Normally when producing potable spirits, most things are distilled again a second time, or a reflux column of some kind is is used.
If you are running a second distillation there is no need to make cuts on the first, only the second. If you still forget to make cuts, you can always dilute it back down a bit and distill again, although you will lose flavour this way (if you are making a vodka then this is desirable).