Bowflex routine

I just bought a bowflex and stated doing the 20 minute better body workout. Its 20 min 3x a week. MWF. I haven't worked out in any form other than walking in a very long time. I am easing myself back into it and I enjoy the 20 min +/- a few minutes that I am working out.

I am using 40 pounds doing 2 sets of 10. I am barely breaking a sweat when I am finished and I have no muscle soreness. I think that this is a good thing for right now but want to get some advise. Should I keep this routine the same for a few weeks and then add more weight or maybe more reps or sets and go for a longer time. I don't want to hurt anything and not be able to do it so I am thinking I am doing it right. Any suggestions would be appreciated!

Thanks,

John