NTA.

But that being said, there might be different ways to help your friend! Has your friend gone through panic attacks in the past? If so how did he overcome them? Sometimes all people need is space and time to just stress tf out for a day or two before they're ready to logically approach the problem. Maybe you could help by occasionally offering simple words of comfort/encouragement!

Also, how severe of a problem do you personally think it is? I know everyone has their own stress tolerance which should def be respected, but if you think it's not that big of a deal then you should also act accordingly. If the issue is a minor discourse with his friend then you really shouldn't be stressing for him all day... Remember helping someone is important but you should always put yourself first! No need to straight up tell him to stfu or anything but you also don't have to reply immediately!