When you set a rule and they explode, the explosion explains why you needed the rule.

A big reaction to a small limit is worth paying attention to, because it usually shows what the limit was interrupting. Someone who has been getting something easily will experience a rule as a loss, and the size of the response tracks the size of what they were getting. It can leave you doubting whether you were unreasonable. The outburst is not evidence of that, and if anything it points the other way.

Hold the limit for a week without reopening the argument, and keep your tone the same as before. If you do not feel safe doing that, tell someone you trust rather than handling it alone.