Holiday ? but how do i get them to allow ?? Advice needed

Basicly im 17 and my mums been going on about me going on holiday with my friends for most of this year and how soon i wont want to go on holiday with them...well the chance has arised to go stay at the girl who i am currently seeing's house for a week while her family go on holiday her nan would be popping in every day to check on her but shes asked me to stay her mum seems to be ok with it too aslong as a bring money for food and clean and tidy up after our selfs. i of course jumped at this opertunity but the problem is my mum is quite protective and was very reluctant to let me stay the night last time. considoring she wants me to go on holiday with my friend cant i count this...surely its alot safer aswell as im going somewhere im familiar with and having her nan check on us. how should i go about convincing my mum my dad is pretty easy on the situations like this as last time he convinced her to let me stay at the girls house a night while her parents where there

thanks for your help :)

Um I think your mom meant camping with your buddies not sleeping with your girlfriend home alone. Please use a condom, there's enough stupid teen moms and preggos walkin around.

my boyfriends mother is crazily over protective of her youngest son. Hes your age. She wraps him in cotton wool and its annoying so I feel your pain as I am always sticking up for him.

Just say to her "if you trust me-you should let me go, Im not a kid anymore and what is the worst thing that could happen". Then say "I get that you are over protective and all but I have stayed there before and I will call you everyday to let you know I am okay"