Got the day off but already booked childcare

[IdiotSandwich]

This is kind of a WWYD and AIBU.
Booked next week off a while ago but couldn't get one of the days off.
Same thing for DP's work, they couldn't get that day off as someone else already had it off.
Boss rang me today to ask if I still wanted it off and I said yes without really thinking. I've already booked childcare and it's too late to change otherwise we'll still have to pay for it. DP also still can't get the day off.
Told DP and he said "Great now you can text childminder and tell her she's not needed any more... that'll be a saving of £XX"
I said "well no... it's too late so DS will still have to go to her or we'd end up still paying for the childcare anyway. I may as well use the child free time to get stuff done"
DP then seemed a bit off and hasn't spoken to me since except to say he's finishing up at work (meaning he'll be home soon).

I feel like he thinks I should just tell the childminder and not pay her when I don't think that's really fair. We're always struggling for money but we had budgeted for this anyway.
I also am a bit worried that I'll get the odd bit done but for most of it just be bored and want to do something with someone. I've asked my friends but most of them are working/away. I really don't like being alone to be honest.

Don't cancel the cm it's not fair on them.

Treat yourself to a proper day off.

I don't like the idea of being alone, I'm awkward like that. I used to but keeping busy is much better for me.
A whole day cleaning doesn't really do it for me either. I've been cleaning for the past two days with DS (HAHAHAHAHA no he's just been making more of a mess in his room whilst I've been slogging away in the rest of the house).
I think I'm seeing it how you guys are seeing it and now the possibilities are endless but I want to maybe drag one of my old friends I haven't seen in ages out. I just feel like my first child free and DP free day in god knows how long should be a fun day.

There isno harm in having a child free day to recharge your batteries.
Grab your friend, go for a mooch and for a nice lunch.

Don't cancel the childminder. They have budgets and expenses as well, it's not fair to them to change it last minute.

I vote for spending the afternoon in the bath with candles and a glass of wine! and maybe your husband if he stops sulking

What do you enjoy doing?
Would a day out somewhere be a possibility?
Maybe a friend could meet you for lunch, or a coffee, even if they are working, and then you have the afternoon to relax, read, sightsee, shop, go to a show...whatever it is that appeals to you.