So you're going to a wedding 6 hours drive away so will be staying overnight. You're really looking forward to the time away for you and your DH (actually you are REALLY looking forward to it and REALLY need it due to just having recovered from PND after being ill for 3 years). You ask PIL to babysit 6 months in advance (you hardly ever ask). They say yes. You turn up to drop off the children and they say "you need to be back first thing in the morning as I want to go swimming".
Now bearing in mind this means that you won't be able to have a drink at the wedding as you'll have to be sober first thing the next morning, you'll have to have an early night and so miss most of the evening party, you'll have to get up very, very early the next day and drive straight back without stopping for breakfast or anything, won't have time for a shower and will arrive back exhausted and feeling like crap.
When you get back they are annoyed with you as they think you should have been back earlier and have decided not to go swimming anyway and so just give you dirty looks and sulk.
How would you feel? Right now am extremely angry and not sure if I'm overreacting.