I had 2 fillings in a molar a week ago since then if anything hot or cold touches the tooth it gets very sore?

Did you get Silver (amalgam) or tooth colored (composite) fillings? sometimes with tooth colored there is sensitivity...or the decay was really close to the nerve and you may need a root c, cant be sure without seeing the x-ray, maybe give it a few more weeks and if it continues to bother you see another dentist