Anger directed at the self isn't something I can really relate to. I do accept my mistakes. I want to help and apologize to anyone I've caused any amount of suffering to. Anger at self seems especially unhealthy... Or, at least it is an imbalance I do not really understand...
I agree, unless it's something overly stupid but, again, if we did something stupid at this stage it means we should take actions not to let it happen again. Most mistakes are not too foreseeable and if we like to make ourselves armoured aginst any possibl emistakes we of course will loose opportunities.
Liek in business, potential gains are proportional to risk. The more you risk, the more you can gain.... or loose.
You do nothing, you won't loose nor gain, you'll remain in a state of stagnation.