Re: I'm possibly out of my depth here technically so apologies for the naive question.
No, your heart rate is an objective measure of how hard your cardiovascular system is working. How you perceive your effort can be very different.
The main point is to fine-tune your training, so you go at the right level of effort. As you train, you should get fitter, so you try to keep your heart rate constant but increase the workload as it gets easier. If you're recovering or unwell you back off the effort. The smart way to train is to split easy and hard intervals rather than go at a constant pace, and the monitor is a tool that helps that. I use a Polar HRM that records speed and cadence on my bike as well as altitude and heart rate. After a ride I can compare the same route to see how I'm progressing (or not...). A bluetooth monitor would be handy as it could integrate with the GPS on my phone.
Whether this is useful to you depends on how serious you are at training.