If it ran for a while it may be that there was jellied petrol in the pump, and it is dissolving. So long as you are using mower fuel to prime it, you will not hurt anything so a couple of repeats of the prime-and-run-until-it-stops trick should do no harm. If it runs longer each time, you are clearing the problem.
While the pulse hose (the other one entering the carburetor) is off, pull the starter and see if the hose pulses air in and out. If it does, it isn't blocked.
If you want to you can check the fuel pump chamber, and the pump intake filter, by removing the four screws holding the black cover beside the fuel line from the tank. That will expose the filter if it has one, and underneath it, the pump diaphragm. If you decide to take it apart, clean the gauze filter with petrol then blow through it, and check that the chamber is clear (no jellied petrol). However I would not do this unless the prime-and-run process does not help. It disturbs the diaphragm unnecessarily, and if there is a filter on the in-tank fuel pickup there should not be dirt on the pump intake filter.
