Your starting point?
First, what is your age? 220-age roughly = target hr. Remember, this is a rough guide.
.Sustained hr at about 85%o of target is ideal for aerobic exercises etc..
Also, if starting hr is 60, then 150 is relatively fast. If resting at 95, then 150 is not so bad. Hr rises more rapidly when you are not well conditioned. If u feel ok, i would not be too concerned.
Consult doc if u r concerned.