In my experience, night sweats always meant I had a fever earlier in the evening. And then it's breaking in the middle of the night, causing me to sweat all over the place. I noticed the sweats can even happen with just a low-grade fever, but it's more pronounced the higher your temp.
Now why you're having a fever can be due to a number of things. But the intermittent nature, again in my experience, means the beginning of a Crohn's flare. I would get in the habit of taking your temperature every night, maybe around 8 or 9pm, over the next week or so and see if you can find any patterns. Then report that to your doctor if you're not seeing any improvement.
For me, it was a matter of bumping up my methotrexate and that got my flare back under control.