I have gone through your problem. Two things can be the cause of this problem.
1. Urinary tract
2. Pelvic inflammatory disease
In females the urethra
is 4 cms in length compared to 17 cms in males. Due this short length the bacteria which is usually present in the genital region can easily migrate up to the urinary bladder
and can cause urinary tract infection which is called as Cystitis
. Urinary tract infection is common in females when compared to males.
In the second case, you have an Intra uterine device (IUD) placed one year back. Since one year you had no complaint like this. But now you may be having Pelvic inflammatory Disease (PID) which can be due to this IUD.
My advice is to consult your gynecologist immediately and get a check up done. Simultaneously she can get an urinalysis
along with urine culture and sensitivity done for you. If your problem is due to IUD, then you need to take antibiotic course and need to get rid of IUD and choose other alternative method. If you have an urinary tract infection, a course of antibiotics is usually sufficient.
Good luck and wish you a fast recovery.