Need help

So I had my last period on the 21st thru the 24th my next cycle was suppose to be on the 16th thru the 19th on the 19th I ended up spotting later in the day usually it starts in the middle of the night or as soon as I wake up but my cycles are always a nice flow this time it was just spotting I could wear a pad all day and have 3 or 4 drops and when I would pee a little more would come but that’s about it I had light cramping it didn’t get worse like normally on day 3 it went away is this implantation bleeding or just a normal period