Help with contract (english)

Hey guys,

I hope you dont mind helping me out with this but im a little fuzzy on dutch employment law.

So a little background:

I was working at fit for free the last 6 months (as a side job) until my personal training career took off. Good news is, it has! So on the 8th April I sent my boss an email saying that I would be leaving and that I understood that there was a 1 month opzegtermijn. Got an email back on the 8th April saying that is fine, he will find someone as soon as possible and that my opzeg termijn will go until end of this month (25th May). My temporary contract ends on the 25th may. I gave notice on the 8th April.

Now, I have two shifts left but because things are getting really busy, I really honestly, dont want to work my last two shifts. I sent my boss another email saying that its getting really busy for me and if there is someone who can take my place and he said that unfortunately he still hasent found anyone appropriate (which I find hard to believe since I informed him now OVER a month ago that I was leaving!!). As a result, It seems I am stuck working these last two shifts.

So my question is, what is my right as an employee? Can I just not work these last two shifts?

I have a copy of my contract and was wondering if someone could translate the aanvang and duur section to see where I stand?.Thanks. Technically I informed him now over a month ago that I was leaving so I should have been released now. Can I just ask him to fire me tonight?

1.1 ider de partijen kan deze arbeidsovereenkomst tussentijds opzeggen, mits schrijftelij en met in acht name van de wettelijke opzegtermijn. De opzegtermijn dient te eindigen op de laatse dag van een kalendermaand.

1.2 deze arbeidsovereenkomst eindigt in ieder geval van rechtswege zonder dat voorafgaande opzegging is vereist, op de eerste dag van de maand waarin werknemer de aow gerechtige leeftijd bereikt.