Background information:
I'm a male, 39 years old and I am very overweight. I have type 2 diabetes that should be in good control and cholesterol and blood pressure should be in good control with medication as well. I'm also taking Asasantin "blood thinner" medication as there were few cases of possible TIA episodes few years ago. I have no diagnosed heart issues but for some days I've had stronger than usual beats of heart, I mean individual beats, not continuously feeling it stronger. Just by examining my own pulse from the wrist, I very rarely find any clear signs of rhytm disorder, but as I visited a doctor, he said that the strong beats may be a type of rhythm disorder of "additional beats" (not sure how to say it in English) that he considered not to be a risk and said that I can just monitor the situation by myself for now.
Most recent symptom:
Last night I woke up to a "vibrating" sensation in my chest area (in the middle or slightly to the left side). Just on the basis feeling my own pulse from the wrist artery, the pulse seemed completely regular and normal even while the "vibrating" sensation was going on (perhaps very slightly fast but nothing very unusual). There was no pain associated with it at that moment and overall I didn't feel any discomfort. A little bit later there was some pain on the left side in the chest muscle area, more to the left side than the vibrating feeling, and in an area that was in size less than the palm of my hand. It was similar type of pain that I have felt before and have associated it with muscle tensions rather than heart-related problems. I felt the vibration on a few occasions during the night as I fell asleep and woke up again. It is possible (but I'm not by any means certain of this) that changing my position in the bed may have decreased the vibration.
Actual question:
Is the fact that my pulse felt regular and normal a good enough reason to rule out the possibility of atrial fibrillation or some similar problem? And if so, would something like muscle tensions explain the feeling of vibration?