My feeling is, pot is too large, not watering enough and it may be getting too much light accelerating the drying rate.
The bad spot on the leaf looks like sunburn. Sharp scissors will allow you to trim that leaf by 50%. But Ursula, and others, have the right idea in my opinion and I agree, it looks dry. The wrinkling is a sign of either too little water or being grow to warm as well.
If you take corrective measures, Phalaenopsis do respond fairly quickly. Root loss takes time to develop and time for us to notice the problem. If it takes weeks to develop the issue, it won't bounce back over night. In my experience, one corrected, Phalaenopsis pump out roots within 4-6 weeks, sometimes 8! But it will recover.
