They're supposed to do it after you've been resting a while usually at least 10 minutes. It's not surprising that you're blood pressure rises at the doctor's office. It's common in fact they call it white coat hypertension
145/95 is high but borderline, you're not that bad off. If you can loose a few pounds and exercise a bit more you'll probably be able to drop the meds.
Blood pressure can vary as much as 30 points in a very short time, your fluctuations are quite normal.