You got a promotion and pay rise after four months and your not happy ?
Join the queue.
PS I did not see anything in your glittering email that sub stanciated a requirement to give you a rise. You are off course eneittled to your statutory inflationary rise of 2/3% but from experiece you have to prove yourself and make results before you are paid more than anything over and above.
Just ask for your next review date , have a list of what you did and how you contributed to certain areas within and outside of your job role, if you do not get what you want at that point well then thats a career decision.