I can't look past the fact this started right after you got gas. What I would do is just get rid of that gas.

1) Get a simple siphon kit and pump it all out.
or
2) Unhook the fuel filter and slip a rubber line over the "output" of it. Jump a wire to the pump relay and let the pump do the work for you.

When you think you have the tank as empty as possible, dump in a bottle of IsoHEAT and a couple of gallons of gas. Wait a day and top the tank off with good gas.