I don't know nutten about butcheren babies, Miz Doodles, but I do know sumpen 'bout cooken. (I know, I know, but I just couldn't help it!)
All kidding aside, it could be that you merely over cooked your meat. Lamb is best, in my opinion, medium rare. I prefer using a slow roasting method for larger cuts, basting often. For smaller cuts, I would quickly brown both sides of the meat over a hot fire then lower the flame and let the meat simmer, covered, until done.
Also, it may be that your lambs were very lean. Good for the heart but not for the juicieness of the meat. How was the flavor? Mild or strong? What breed were they? What were they fed while dry lotted? Inquirering minds want to know.