Based on your description of the plant, I would not cut the spike either. If the yellowing leaf is one of the bottom ones, that's most likely natural, too. Phals grown in a home sometimes don't have a large number of leaves. They will put out new leaves and roots in their own time. Since you're new to this, you'll learn as you go along how to optimize your conditions and care so as to maximize growth and blooming, but in the meantime, congratulations on getting your first reblooms!