If you are reaching out for great schools like Ivy league stuff, you definitely get a great subject GRE. Even with a tremendous CV, publications, very strong recos and 97 and 95th percentile gre my chances of getting into such a school got hammered. I'm going to UMDNJ, but it's not the same anyway. So get subject GRE now!
By the way, I'm an international student, so I'm not sure if this applies to the domestic ones too, so...
Some of the universities choose to do the skype interviews earlier than the domestic ones; others later. Also there are universities like UVa (virginia.edu) that is infamous for late decisions. I am not sure about the universities where you have applied. I'm from the same background (same country, same stream) and I have had 4 interviews yet with one acceptance and one rejection. Although it is getting late, there's one thing for certain: you are still in the hunt; at least in the waiting list (since I guess a few universities have already sent the first batch of acceptance letters). It's good news for you that you were not rejected outright without an interview in the middle of January of early February (some candidates receive their rejection letters then). It's bad news that you are yet to have any interview. But then again, in our stream selection:interview ratio is high (1:4 to 3:4). So if you are asked to sit for an interview, you would definitely make it (because it is too late). Also the universities where you have applied are not too high ranking; that means many of the first choice candidates of theirs will turn down the offer. So hang on there.