Well done man! Awesome work. We've all forgotten the safety at some time or another!!
Definately go back for the stag, but don't leave it too late. The sooner the better in my opinion. In three weeks time the place will have a lot more pressure put on it.
As for burying the guts etc, good on you for being tidy, but don't worry about it in the future. Stash it in some bushes out of sight and away from any water source and kick some leaves over it. At this time of year it'll be gone in a couple of weeks!
And as far as spooking the deer go, I wouldn't be too worried about that either. I've shot deer on clearings grazing within a few metres of guts from a deer I shot the night earlier and have even shot them on a clearing the same morning a chopper had been through shot six and gutted them on the same clearing. The gut bags were still steaming!
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