Hi
Apparently I've always had a low resting pulse which maybe partly because I've always exercised or I'm just a sleepy lazy Aussie Koala! I've just swapped from UP to Fitbit and I'm getting a slightly different reading partly because they record it a little differently. I was a bit stressed a few weeks ago and it was coming in at 65 per day, now it's down to 59-60.
Fitbit records an average during the day during rest whilst UP takes it before you wake up in the morning which is when you are supposed to be at your calmest, before the days worries kick in! I think you'd have to wear a medical one for 24 hours to get a really accurate reading.
Last year I was worried about everything in the heart dept but I spent a day cycling around an island, up hills etc and didn't keel over so doc said nothing to worry about! Stupid thing was I'd only had an EGC a few months before and all was fine. If you walked 15 miles and up an incline with no ill effects I don't think you've got too much to worry about!
I've got the Alta HR which also measures Vox2 or something, so it calculates how much oxygen you are using efficiently when you exercise. The higher reading you get the fitter you are. It keeps telling me mine's excellent for a woman of my age (I think that's a compliment!)
Maybe have a check up at the docs but if you've always had low blood pressure and pulse the chances are it's just normal. I think they worry when it suddenly goes low or high. Take care!