Switching Time Taken

I’ve been taking 25mg of Zoloft for a couple months now. A week or so ago, I forgot to take it at my usual time (noon), and didn’t realize until 8:30pm.

I took the pill then, but I wasn’t really sure what to do for my next dose. I assumed I shouldn’t take more than one in 24 hours, so I have just kept taking it later.

It’s been helping me sleep better, but I noticed I’m getting headaches again like when I first started taking it. Is that normal? Also what are you supposed to do the next day if you take a dose late?