My Wisteria was pale

If you cut it back too far down, you may have compromised or killed off the grafted part - that would mean what is growing is off the rootstock, which will be wisteria, but not the variety you bought, and which would have smaller, pale flowers. That is why I asked how far down you cut it...

Pale and small flowers usually means the plant was stressed; though also signs of a sulfur deficiency the leaves would be distorted as well in that case.