I used ExifTool to extract image dimensions from the files:
exiftool.exe -T -r -FileName -ImageWidth -ImageHeight -FileSize * > data.csv
I uploaded the csv into a google spreadsheet and i generate a graph from those values.
Since the jpeg should be no more than 1200px on the largest side, you can easily spot where i fucked up. If both ImageWidth and ImageHeight are over 1200 (two cases) it means i forgot to resize the pic. If only one of ImageWidth or ImageHeight is over 1200 (another four cases) it means i wrongly resized a portrait pic as a landscape one or the other way around.
The same ExifTool is used to check for bitdepth:
exiftool.exe -T -r -FileName -BitsPerSample ./* > data.csv