I went out with this girl for the first time (first meeting also) this past Sunday when we went ice skating (good opportunity for light kino) and then to a coffee shop to warm up and talk a bit more. Everything seemed like it went well, entertaining conversation, enough kino but not too much, and plenty of smiling on both ends. I walked her to her car and we hugged, said we had a good time, and as I was about to say "I'll call you soon" she said "be sure to call me". Which caught me a bit off guard but whatever she gave me the green light so far as I could tell.

Two days later (tonight) I call her to chat her up and set up a second date. She didn't answer my initial call but returned it a few minutes later when I almost immediately got "I called to say I don't have much to to talk". I said "No worries, just give me a call a bit later when you do have time." And here is where she begins and tells me that her schedule (work and grad school) just amped up to where she was busy for the next two weeks and she said she was going to lay low on dating currently and that she would call me if anything changed.

I know I'll get the responses about "if she was interested she would have made time" but I've dated grad students before and they are loaded, especially if they work a job. What approach, if any, can I take here? I know to let things cool down but should I even try again? Let me know how to proceed.

This is a risky one but I didn't try it enough to set a fail/success ratio. And it is simply : Freeze-out.
I'm a freeze-out type of guy and I do it a lot always with success ( But still, there Gotta be a fail rate to this ) A girl did this to me when I was like a month into The Game, and I just freezed her out, totally. She talked to me again two months later ( Patience is a virtue ) and I have changed for the better ( At least from her point of view since I got like 5-6 months into The Game, stiiiill learning..) But try it.

Leave her a friendly message before you do though. Just an innocent " Let me hear from you when you finally decide that was a bad idea " or whatever, just add your touch. Cause' if anything you just cut connexion cause SHE " has an amped schedule ", you're just a soldier following orders. And in the other hand, this will make her miss you especially if the freeze-out is done after a peak. Be cautious with it though.

Good luck, man