I think I found your answer. Lady in Red blooms on old wood. Here is the snippet:

�Lady in Red� Hydrangea
Hydrangea macrophylla �Lady in Red� #15,175

Pruning is not necessary, especially since �Lady in Red� is a compact form. If you want to prune to improve the shape of the plant, be careful to prune shortly AFTER flowering because flower buds are formed on the previous season�s growth. Prune these hydrangeas only in the summer before July/August to be sure that you are not cutting off the stems that hold the flower buds for the next season. This hydrangea blooms on OLD WOOD, stems that have been on the hydrangea for at least 9-10 months, and sets its flower buds in late summer/early fall for blooms the following spring.

Sometimes some hydrangeas will defy this general rule, but for �Lady in Red�, be careful of your time of pruning to ensure blooms in the next year.

For older plants, older than 4-6 years old, the general rule is to remove about a third of the old wood by cutting them down at ground level during the summer. This allows for more light into the plant and it helps revitalize the plant�s new growth.

Here is the website:
http://www.ladyinredhydrangea.com/care_pruning.cfm

It looks like it may be too late for you to snip, and that perhaps you should leave your baby alone.

Hope this helps.

Donna