If so, you may have spread the glue too thick, not waited long enough between coats, or a sudden drop in temperature or gust of humid air may have occurred. Someone may have opened the door, or you may have leaned too close and breathed on it. Plan to stay in the room until finished. Glues and solvents are flammable. Use in a well ventilated area.
Fumes can be overwhelming.
A carbon filter respirator is recommended. MEK solvent smells, but is relatively safe. Do not use Toluene. Inaccurate measurement will weaken the glue. Once opened the accelerator cannot be kept.