That does seem a lot, but, must be eating well and is not uncommon. as long as your water parameters are good and the molt is complete, I would not worry if you notice the shrimp is getting larger and the new skin looks good. the old discarded skin should not hurt anything but I always removed it when I could without putting hands in water (long tweezers, or tongs). It was not unusual for a 2 to 3 week molt in my last system where I kept 6 shrimp (Lysmata Amboinensis). hope something here helps.
