It's still roughly 13/14 weeks a year, you're not marking/planning for 10 of them (which is what you'd need to be to equal the average holiday allowance of most of us)
Honestly mate you're doing quite a bit of work over each half term. The summer maybe only one week from the five as you need it to get ready to go again but the others you have a lot to do. Next half term I will probably only have two days off to relax.