It sounds like, since you are still shaking a bit, you are still not quite conditioned in for the bow. This can affect form, which can detract from performance. Also, there is the possibility of tuning issues which can affect performance also. 45# in the hands of a proficient archer can be very deadly on many types of game, even though I admit I prefer 65#.
What kind of penetration test did you use?
Don't go up in poundage until you are fully comfortable with the poundage you are currently at. The answer is training and conditioning.
As for shooting 80 yards on a 3D course, that's just plain nuts, even for the wheelie bows. For me, it would be a waste of time. I have never shot a 3D course with trad shots over 40 yards and most were a lot closer.
Most of the trad guys I know limit shots to 15 or 20 yards on game. 45# is sufficient at those ranges for most of what you may hunt, but I would want more if I ran into a big bear, like a .45-70.
Don't get discouraged as this is a skill developed over time. Just keep working and stay focused. It will come.