Is this implantation bleeding?

So this bleeding happened 14 days after ovulation according to this app and if it was a period it was 3 days late and it’s only lasted 4 days and my periods are usually sometimes 5 but mostly 6 days long and also my periods are always on the same time every month I’ve never been late on a period. This bleeding was somewhat heavy but not as heavy as my periods usually are but I wouldn’t call it light and it was more in the medium category I guess for example I didn’t need to where a tampon and I wore a thin pad throughout the day and even to bed I wore a thin pad which usually I can never do and the “medium” bleeding happened for 2 days and the last 2 days were very light almost like spotting also I did experience cramps and I don’t now if implantation bleeding causes cramps or not. Also recently I’ve been eating A LOT and I’ve been nauseous and I’ve thrown up I get headaches all the time and I’ve been very tired