Worried about a DVT reccurence and PE

So I had a provoked DVT from knee surgery 2 years ago. This past May my calf was hurting again so I had an ultrasound on it and it was good. Then a month ago I was having some chest pain while breathing and went to the hospital and had a d-dimer test which came up with no evidence of clotting. Last Friday my other calf had been in pain for about a week so I went and had an ultrasound on it and it was good. We'll I still can't get this thought out of my head that I have an undiagnosed PE. Does anyone else have any advice in dealing with this? I shouldn't be worried like this after so many positive tests but it is just getting to me.