Timing belts have teeth so it is impossible to screech a timing belt on any pully except the tensioner pulley which is just a free spinning wheel keeping the belt tight.Since you had to remove all the other belts in the process of replacing the timing belt, the most probably cause is one of those belts, i.e. alternator or A/C belt. Check the tension on those before you draw any further suspicion on the timing belt. If the engine runs fine, you know you have the timing set properly and if you adjusted the tension per the manual, the auto tensioner should keep it tensioned to specification.You put the belt in just fine... Check the others!