This is both an answer to your question, and to others suffering from skipped beats in stressful situations.
It's very likely you had a short (non sustained) tachycardia run. The question is, what makes you so sure you have PVCs (and VT) and not PACs (and SVT)?
When you get a short run during exercise or stress, it's extremely more likely to be SVT than VT. PAC salvos are fairly common among young people. VT runs are not, though a couplet or triplet may occationally happen in people that are very bothered with PVCs. This is usually not caused by the re-entry mechanisms that make VT dangerous, and is usually a benign condition.
Even on Holter montors, it may be difficult to sort out PACs from PVCs. Computer based interpretations will determine all "wide" QRS complexes as PVCs (>0,12 sec), and as far as I know, most PVCs in younger people registrered on Holter are actually PACs.
Of course, you can't be sure if you don't get this monitored, but my guess is that you had PACs and a run of SVT.
Sound like some bigeminy or maybe trigeminy to me. I thought I was having PVCs "in a row" and turns out it was bigeminy, It felt like they were consecutive, but turns out there were normal beats in there. I get couplets and triplets on a daily basis and I have found that I can't really tell when there are two or three VS one and I feel EVERY PVC. Bigeminy can make you lightheaded(I get this all the time). My PVCs went from 1 or 2 a day to 4,000 litterly over night and I'm only 27, so yours could just be increasing a little(also not unusal). If your PVCs are increasing during exercise, that may be something worth mentioning to your cardio. I was told just today by my EP , not to worry about the "runs of PVCs" or the numbers:) In fact I was told that in a normal heart, VT is not usually dangerous, especially NSVT, which is less than 30 secs.Hope this helps!