I suffered quite badly with anxiety a couple of years ago and had lots of physical symptoms including dizziness, derealization, panic attacks and pressure feeling on chest. Symptoms have eased and I haven't really had a any for months.
However, over the past couple of months I've had three or four tight chest incidents when I've been outside. The first time I was walking up a hill and got palpitations and chest tightness. I shrugged it off as one of those things. Then I discovered I'm pregnant and had the same episode on the same place on the same hill, but really struggled to breathe for 15mins - could only shallow breathe and my chest felt very constricted like it was being squeezed.
I went to the doctor and I've had blood taken to check thyroid function and cholesterol levels and am waiting for results. He took pulse, blood pressure and listened to my heart and chest and said everything sounded fine. I told him I was convinced it was angina as had been googling
. He said possibly stress. Not had blood results yet as got call telling me the nurse hadn't labelled them properly so have to go back and get them done again. Hate having blood tests as well 
The same thing happened again today when I was out walking the dog. I was stood talking to someone then set off the walk away and the chest tightness occurred - probably lasted about five minutes and could only breathe quite shallowly.
I'm really worried I've got some sort of awful condition and have been googling this evening and have scared myself silly - keep crying and worrying. I haven't felt anxious recently - no more than unusual - but am now incredibly anxious because of this chest issue and the fact that I'm pregnant. I have asthma but it doesn't feel like asthma.
Sorry for ramble, just needed to let it out