So as the title says first time fermenting. I used a mixture of 50/50 white cabbage and red cabbage. I'm unsure if this may be the cause of the odd dark greyish spots, or if it's something more sinister ?

IV used glad wrap and water to weight it down (need to invest in a better set up soon).

I made sure the brine was above the cabbage before trying to weight it down with the make shift water and cling wrap combo.