Yes that happens a lot. That's why I like to use the funnel to fill the pre-heating pan as it gets quite fidly to reach. You can pour it over the top as well, but that just increases the risk of spilling the fuel.
It's also the reason I wait until the end of the pre-heating burn before I pump pressure into the tank.
And as I say, if you fail to pre-heat it enough you get what we in the Norwegian army called a *"Home guard fire"....always a mark of ridicule :-)
Here is a sNorwegian soldier messing it up...probably during training as he has a stack of them behind him :-) Atually, just spotted his arm patch...he IS a Home Guards man :-)
But lets not ridicule the home guard...the His Majesty the Kings Guard seem to have some problems too....