The effect on mental capabilities is not any worse than the effect of other painkillers such as oxycontin or morphine.
Or the wooziness and mental slowness of not being able to eat for days on end.
I'll give a personal example- I'm currently taking prometrium, a progesterone supplement, twice daily. I'm taking it to prevent another miscarriage. It makes me completely and totally looped. I feel like I've had 3 glasses of wine. I'm seriously like a drunk- slurring words, feeling very "loose" in my muscles, etc.... until the overwhelming tiredness hits and I go and sleep it off.
You're probably also reacting to the natural progesterone in your body.

What you describe is pretty much how I felt for most of my pregnancy. Just wait until the feeling while you're nursing the wee bairn...that is a serious lull feeling, so calm, so peaceful...
It is also far, far more difficult to catch a contact high than some previous posters would lead you to believe. (Trust me I've tried!

)
Must be your particular system. I've always found it very easy to get a contact high.
Until my mom quit smoking everything when she was 35 (I was 10) she and her friends would smoke around us. And...I've just now figured out why Thanksgiving dinners took so long, OMG...I've wondered for years how we all used to eat so much.
I know it sounds terrible, but she was a wonderful, marvelous mother who was a hippie in SF in the 60s, and she worked 6 days a week to support us, and if every so often she needed to giggle with her friends, that was OK. Just...that and the cigarettes she started at 15 didn't do much for her asthma, which is why she finally quit smoking ANYthing.
And it sure did cause ME to be a straight arrow! But it made me kind of strange at my private university filled with trust fund rastafarians...they were acting like my parents...borrrrring!
It's funny, I'm very much against being around my peers smoking things like this, and finally put a moratorium on dating people who used it b/c they were SO useless in relationships, BUT I'm all in favor of
full drug legality. Most prescription drugs scare me far more than others, and it makes no sense that there's the magic line between OK and not OK.
Glad that those who have been prescribed it can get it without being arrested.