yellow leaf - I'm in a panic!

I have a phal. It has five leaves. The bottom two are getting a little wrinkled and one is starting to turn yellow.

The plant is currently growing a flower spike for the second time. The spike has three branches with a total of 16 buds. None have opened yet, but you can imagine how excited I am about the success of this second blooming. It's been about 9 months since it last bloomed.

What should I do about the leaves? I am very careful not to over water. I always stick my finger way down and if it feels even slightly damp I wait. I use orchid fertilizer every time I water, as recommended on the bottle. I never let it sit in water.

I also have five other phals in the same place, all doing great. Some are blooming for the second time and several are also growing new leaves. This is my one problem child at the moment.

If something happens before all those buds open I'll cry.

What should I do?

It could simply be normal leaf senescence, but as it's two at once and they're wrinkled, I'd still vote for issues with the root system.

When was it last repotted, and into what kind of medium?

Most root issues are due to suffocation - sometimes caused by overwatering and clogging up the pathways for air to reach the roots - but time and decomposition can also lead to the compacting of the medium, which does the same.

At first I was going to question you about the fertilizer formula and concentration at which you use it, but if the other plants are OK, that's not the likely culprit.

One last thought - are you "forcing" the plants to rebloom in order to get more flowers? If so, you might have simply weakened the plant.