Hiya, sorry you're feeling this way but it's totally normal my cycle usually last around the same time as your and i'm a lot older than you 27 years old almose 28 btw. Interms of improving my cycle i haven't done much i just learnt to accept it, i know at first you feel like the odd one out but i learnt to accept it for what it was. And please don't feel pressured by the doctor to take the mini pill, as it's your body and your choice. In terms of emotions i understand where you are coming from cause i have the same issue but as time goes on you'll learn to accept the normal- i have been on the pill but not in regards to the matter you've mentioned however it does temporarily stop the cycle, but you may still feel emotional etc like you would when your cycle is on it's way or when your on your cycle, the emotion doesn't go away just the cycle. But when i came off the pill it took a while for my cycle to come back which is normal however once my cycle arrived it was still the same as before (but saying that everyones body is different). you'll have a lot of lows than highs nearer to your cycle but that's normal too. It's completly normal for us females to have shorter cycles than others doesn't make us odd, or strange it's totally fine x
i hope this helps and wishing you all the best in life x