Alternatives to freezing? (dental and hospital)?

I have had a bad experience with a freezing agent just recently. I was at the dentist and they gave me the shot which was fine and it didn't hurt or anything because I had a numbing gel on my gums but what happen after wards was what got me worried about the next time that I might possibly have to get a filling. I was overcome with a mass wave of nausea and cold sweat also my arms and legs felt very limp. I had a similar experience 2 years ago when I had to have an abscess drained and they gave me a local anesthetic and I became nauseous. What can I do? I hate nausea with a burning passion of hatred it just makes me feel horrible to the point of it almost being a phobia (which it isn't.)