Nothing wrong with that, the whole point is to do what works for you whether that's working on faster times or just getting fitter or just keeping active when it's dark and cold! None of us are going to the Olympics!
You sound quite similar to me in attitude. I can give all this sensible advice but I also am a "doing less is giving up" type person and freely admit I probably go too fast and too hard on some sessions, but it works for me. That's why I said *if* you are getting discouraged think about changing because the most important thing in my opinion is to do whatever makes you want to come back tomorrow.I planned to do an easy bike ride today, before the temperature plummets again, then resting tomorrow before more exercise (erg is scheduled) but in the end that's not happening. I'm tired, and even a really easy bike ride just seems to be too much. Not even watching Omloop Het Nieuwsblad was enough to inspire me. But I started some more seeds for my vegetable garden, so I guess that's a win, eh?
Now, having said that, your comment about your bike ride stands out to me. If you are too tired for what is presumably an enjoyable, relatively easy activity then it may be a sign of overtraining. Maybe just due to doing 4 days last week, but maybe it's been building over the past few months. I'd suggest keeping an eye on it. If it's a one time thing, stick to 3 times a week. If it feels more constant consider a week off to recharge