I am assuming that before your fatefull trip to the gas station, your ped ran just fine.
You know you have good fuel flow and provided you assembled it correctly, you know you have a clean carburetor.
On the assumption that the only change you have not yet reversed, is the new tank of gas. Drain it out and replace it with fresh mix. This may not be the problem, but at least you will have eliminated the possibility.
AFTER you have done this, if you still have a problem, partially choking the carburetor is not a solution. If you have to do this, you either have too little fuel (partially plugged main jet) or too much air, see Fred's post and check the fit of the carb to the manifold for air leaks.
Do not loose sight of the fact that the ped used to run ok, so you do not have to modify anything to make it run, simply get it back to the way it was when it ran .