fuel gauge

I was going to say to check the tank fuel float, it probably broke. And if you're having trouble putting gas in the tank I'm guessing it's time to remove and clean out the tank anyway.

For the fuel gauge. Crawl under the gas tank and remove the sending unit wire plug that is at the front of the tank where the fuel line come from. Twist it back and forth a few times then do it while pulling.

Once the plug is off, ground the wire to the chassis. Make sure you have a good connection. Then turn the key on and see if your gauge moves toward full. If it does, the sending unit in the tank is bad.

If you still have no needle movement, you will need to remove the dash gauge cluster to test the fuel gauge. One side should have power (maybe 5-12 volts--test with a voltmeter with the key on) and the other side goes to the fuel tank. If you can determine which one goes to the tank, you can short that connector and see if the gauge needle goes to full. That tests the wire from the tank. Remember that you will need to turn the key on and since you will be making things live under the dash you need to be careful not to short things out.

If you have no voltage at the gauge, then the CVR found on the back of the cluster is bad--relatedly if it is bad your temp and oil gauge should also not work.

As far as filling the tank, there really isn't any correlation with the fuel gauge. My guess is that your problem is the particular gas station pump that you used. Modern gas pumps try to pump an incredible amount of fuel at a time to try to lessen your time at the tank. Older fuel systems cannot always handle it and gas will come flying back at you.