I have heard that almost everyone carries the strain of the herpes virus that causes cold sores/fever blisters and that it just acts up in certain people. I have had them since I was a kid. I have found that taking L-Lysine supplements decreases the severity and likely hood of getting them. I have also started using
Morgan's Lysine Lip Balm as well (that alone usually clears it up in a couple of days). I can find the lip balm at our Walmart. The Lysine doesn't work on everyone, but it might be worth a try if you are worried about it. I do know for me though, that using the Lysine has made a world of a difference in how often I get and how severe my cold sores are though! So wish I would have known about it sooner!!
(((HUGS))) I hope that's not what it is, but hope that if it is the advice I gave helps a little.