Typical die-off symptoms include headaches, going to the bathroom more and a variable worsening of other symptoms you have.
You should experience die-off almost immediately after taking a yeast killer, like x-virgin coconut oil. A yeast killer won't work effectively unless you are following an anti-yeast diet, but you would still feel bad not long after taking the killer.
If you don't feel bad after taking a yeast killer, then it isn't working. Either yeast is not your problem (your symptoms certainly point in the direction of yeast), or you need another killer.
I recommend you consider the possibility that something else is causing your trouble. For me, my yeast trouble was related to heavy metals (in my case it was mercury from my silver fillings, but there are other metals and other sources).