Hi Matthew,
Congratulations on starting to build transformers !
Please would you upload a picture and/or diagram of your transformer, and give us the following specifications:
The size (diameter) of the wire you used;
The length of the wire;
The number of turns of wire on each of the primary and secondary windings;
The input and output voltages.
Then we can do the necessary calculations and we will probably be able to diagnose your problem.