Am i being ungrateful or do i have reason to be upset

So I recently turned 18, I didn’t ask for a big party or actually anything in particular. For context my older sister is in uni and my mum is financing it, because of this I don’t ask for money, I commute to sixthform by train which is 20.95 a week and my dad gives me 21 pound so I have 5 pence left, I wake up around 6 to get me and my sister up since my parents are not at home from 3am-8am due to a gap in the work schedules, since I get up quite early and then commute 40 mins to school I don’t really find time to take packed lunch but maybe once every 2/3 weeks I’d ask for 5 pounds lunch money for the week. I’m a black girl so I need to get my hair done which I appreciate my mum paying for every 3 months or so and also my weekly driving lessons. With all this in mind I chose not to do or ask for anything on my 18th. To my surprise, my mum gave me 300 pounds!! I felt so guilty accepting, I told her it was too much and I’d be happy sending half back or so, she said, “300 isn’t much since i could’ve gotten you an upgraded phone which would be more expensive” i said “should i use half to pay my driving instructor” since i had a driving test 3 days later and my driving instructor requires 150 for her car and an hour lesson before, to this my mum said “no I’ll pay that, this 300 is your gift and Ik you don’t ask for much” I felt guilty accepting but I didn’t contest it after. Fast forward the day of my test, my mum was annoyed in the morning and she said I had to use the money she gave me, despite previously agreeing to this i didn’t find this fair so I calmly spoke to her about it 30 mins later and she said “if you haven’t misbehaved there’s no reason why I won’t reimburse the 150 pounds”, this eased me and I trusted her, since then I haven’t asked for the money until today, I know it’s trivial but I’ve been wanting to do it for a while - getting my lashes done. I spoke to my mum about it and she said, “you’re not getting your money back, what am I gonna use to pay for your hair and your driving lessons, even so you’re too young for that” firstly, she promised she wouldn’t make me use the money on driving lessons because what would be the point on giving it to me?? Hair I do understand even tho she did say it was my spending money I do understand hair, I just don’t like being lied to and false promises especially when I’ve been trying to cut her costs, wearing beaten shoes to school, not buying lunch outside, walking instead of bus, and to say I’m too young is annoying also because 1. I’ve gotten my eyelashes done before with her permission and 2. I’m an adult now so like what??? Its eyelashes???? I go to uni in less than a year, I’m not too young to move out but I’m too young to do eyelashes so clearly she’s just saying that to prevent her not having to fulfil her end of the promise but I just hate being gifted to have it taken back and I know I’m probably being really bratty and if I am please say so, but whether it’s lashes or not, why give me the illusion of a gift if I’m not actually getting the entire gift?