Having mixed drinks about feelings...

Preface; I have an amazing relationship with my man, we are very open and communicative, we rarely fight, we have the same goals, plans, the whole nine.

That being said, this is not a post to complain about him.

His birthday is in a few days. Also happening is our anniversary.

Now, a few weeks ago when I hinted around to doing something for his birthday, he explicitly said NOT to, that he doesn't celebrate his birthday and he would not be happy if I did anything. Instead, he said he would much rather focus on celebrating our anniversary.

Okay, deal.

The last 2 weeks have been stressful so there hasn't even been talk about planning an anniversary anything, I'm okay with that, I understand his side, so I'm not even worried about it.

With that in mind, I decided to make plans. I have been working hard and squirreling away money so I can take him out, to enjoy some spoils from me, relax, and over all have fun. With everything going on, we don't get out much, if at all, really.

I'm going to note here that he doesn't know about my plans, so with the next part, he's not being selfish, or an asshole.

Last night we were hanging out with our friends. He commented how our anniversary and his birthday are on the same day. Our friend got excited! The next thing I know, friend is throwing out ideas to celebrate, all while my man says "I don't want to do anything for my birthday!"

And it seemed like that was solid until friend suggested paintballing. Now man is interested, excited even, they're tossing out game plans, they're rehashing stories from times before, they're all but clinking beer glasses!

It's a mad house.

So now the plan is set: the four of us go paintballing (friends are a couple), grab some drinks, and come home and hang out.

Here's where the problem rests: 1, I can't go paintballing. Getting hit with them hurts worse than a normal person, I bruise super easy, my job is physically demanding and I'm already in chronic pain, so I'd more than likely miss work if I go.

2, it's already really cold where we live and I don't do well for long periods of time in temps below 50.

I haven't told him yet. He's all set for the day.

I'm not sitting here expecting him to cancel and stay with me.

I'm asking for advise on how to approach this without being super emotional or potentially causing a fight.

Should I tell him about my plans, or should I leave that out?

All advise is appreciated, thank you!