Should you take a break from writing?
Writing is, at its core, a creative process (especially where fiction is concerned). You can't force creativity. Or at least you shouldn't. If you try to force your writing, your writing will be... well, forced.
A rule of writing I've always followed is that if things just aren't working out or you don't have the interest you did yesterday, go do something else. Do something which requires engagement on your part, like playing a game or talking with friends. But don't, say, take a run in the park. Don't be alone with your thoughts, because they will invariably turn to your writing. Force yourself to confront something else for awhile, then come back to your writing when you're ready.
Just make sure that you write something after a week, even if you immediately throw it out. Without practice, your writing will begin to stagnate.
While it is not relevant to this answer, one thing I wanted to note was something you said in your OP:
sometimes writing gets in the way of much needed reading time.
This is a warning sign to me. Reading is very important. It is one sure way to become a better writer (assuming you are selective about what you read, of course). But your phrasing suggests that you find yourself wanting to write during your set 'reading-time'.
Whatever you do, do not fight this. If your interest in your writing is up, and you feel like it's been sub-par lately, the last thing you need to do is quash the urge to write when you have it.
Reading is very important, but it can be done at virtually any time. Writing cannot. Writing comes and goes as it pleases. Writing doesn't care about your schedule, or your sleep patterns for that matter. You should not be trying to fit writing into your schedule. You should be trying to fit your schedule around your writing. If you're serious about writing, that is.
Now if your writing is truly just an enjoyable hobby, then my only advice to you is this: relax. Don't worry about your writing being on 'par'. Don't grade your writing. If you write for fun, that's all that matters: writing. Write what you want, when you feel like it.
The only one you need to please with your writing is yourself. And if the act of writing is enjoyable, then you're already there.