Crossfit mixed with PT / Endurance

[Neg]

I've been doing crossfit for over a year now and really wanted to start boosting up my training. I'm concerned however about "over training." For the past 2 weeks I've been doing Crossfit in the mornings before class, and then transitioning over to Stew Smith's book in the evening. I really want to get my running times down and get used to running long runs as well as swimming. I've done the 12 weeker before, and it was pretty time consuming...so it's difficult to fit it all in one day with classes etc. I'm just wondering if all the time put in to this kind of training is worth it, or if I'm ultimately hurting myself by over training. Right now I can't really tell because I seem to be doing just fine, I'm eating right, sleeping well and drinking a lot of water. Then again, its only been 2 weeks. I'm just concerned about where I'll stand 5 or 6 weeks from now.

Does anyone have any input as to whether or not I am going too far or maybe has anyone done something similar?

Thanks