Spotting vs period

Can someone please tell me the difference between spotting and period? I tried looking up the differences but still in a way confused, the last for sure period I had was in September and a couple days ago I started having what I thought was spotting because it doesn’t fill up a pad and it only comes out when I wipe but the color is like a brown/ dark red. Usually my period is a regular red and it’s heavy plus I haven’t had many of the pms symptoms I usually have like sore boobs, that never fails to follow but not this time, I only have had dizziness and minor headaches but that’s about it at first I thought it was just spotting because of how much but now I’m not sure bc of the color. I’m just very confused 😕 TIA