Welcome!
There’s no ‘right’ or ‘wrong’ way to do the ramp test really. Ultimately you just have to keep pushing for as long as you can. If you are not that internally competitive or you are not that much of a masochistic, it can be a challenge to push yourself far enough to get a ‘good’ result. It can be helpful to have someone cheer you on or some other motivation like music to help you push yourself.
That being said there are a lot of things that can cause a low (by your expectations) result. For example, I tried to do my ramp test at the start of this week but I knew I had three nights of bad sleep and when I started the test I knew almost immediately that my heart rate was climbing too fast. These are things you start to get a feel for when you have done a few tests. To really have your “best result” means you are well rested and primed for it.
In summary, don’t feel to disheartened. If you were completing workouts at 149 and not struggling, then that is a clue that you were in a good place and the test result is probably low.