Ambiguity(with minor conniption fit)

So Stephen Hawking is talking about humans having to go into space to survive in the long run (which I agree with, unless you define "long run" as when all humans die out, in which case I don't). He's talking about how close we (meaning scientists; I certainly have nothing to do with it) close we are to solving the origin of the universe, the meaning of life, etc.. And he's talking about how he wants to understand women. A joke, sure, but one that resonates with people from both sides of the gender aisle.

I have never bought into the whole "I don't understand women" thing. Not saying that I do understand women. But I don't think there's much to understand about them as a class. There are almost certainly biological and cultural influences that are shared by the majority of the women that I will encounter, but I think that I have a reasonable grasp on these (or at least working hypotheses). There are two associated sources of mystery, though, one at a more macro level (people in general are confusing) and one at the micro level (each woman is a unique specimen, with her own experiences and personality that influences decisionmaking). Neither of these are because they are women, though.

So I reject women, as a class, being particularly ambiguous. But I fully, achingly, embrace that women can be ambiguous on an individual level.

To wit, here are paraphrases of two conversations I've recently had (with two different people, across different media, with some time lapse for the reading experience):

Exchange 1:

Me: So I'd like to hang out some time.
Her #1: Sounds good.
Me: I've been having trouble catching you. Is there a good time to call?
Her #1: Call any time.
Me: ...

Exchange 2:

Me: How about dinner tonight?
Her #2: Can't tonight. I'll call you later.
[fast forward 5 days]
Me: Does "I'll call later" mean "bug off"? Or what?
Her #2: I've been sick. Call me later.
Me: ...

Now, I don't need SPECIFIC information (call me on the second night of the new moon at 8 minutes before nine of the clock) but "any time" and "later" are ambiguities that could EASILY be avoided by saying things like, "Tuesday".

I'm not complaining, mind you. I know that I might be oversensitive to ANY lack of clarity in response to these types of questions (I'm not experienced asking them). And I'd prefer an open-ended "yes" to a "no" in almost every case.

But ... *waaah*! I want clarity! And I'm frightened that pushing for it will seem the act of an insecure and emotionally immature man who's desperate for female companionship. (Of course, I am an insecure and emotionally immature man who's desperate for female companionship, but I don't want THEM to know that...)