The most common cause of unusual body odor is a skin infection.

An ammonia odor is caused by infection with Helicobacter, the bacteria that causes stomach ulcers, or by eating a high protein diet.

As your protein intake may have risen it is most likely that and not the bacterial infection.

When you take in more protein than your body can use immediately, your body strips ammonia from protein to make you smell like ammonia. The smell of babies diapers!

You do not need to increase your carbs but should check what is the adequate or recommended protein for you. Low carb diet does not necessarily mean high protein.

The smell of ketosis is more of an acetone smell.

A really excellant low carb book is Protein Power. This will give you the adequate protein levels for your body.