My first symptom was night sweats just as you described night after night, there's no telling how long this phase will last. You're probably early on in perimenopause if you're still regular. My sweats started 3 years ago and I'm still peri.
Do they bother you? Might be worth chatting to your GP, hopefully a good one, and even if don't want hrt now you might later. Migraines don't rule hrt out, just a matter of finding the most appropriate type.