Cystits hell is really impacting my daily life.

Patient: Hi I have been suffering for years with cystits at least once a month, almost usually from intercourse but sometimes i think my constipation (lazy bowel, self diagnosed but rarely functions) may cause it also, i urinate immediately after and cleanse with water however this still doesnt stop a flare up. The burning starts and fever hits which leads to shakes and the constant urination. It also seems to feel as if there is alot of pressure build up towards my back end. When it starts i never get it mild and need antibiotics to treat it immediately. I have had it twice this week and it literally is taking toll. Could you recommend any further investigations my doctor only ever perscribes me antibiotics?

Symptoms: Burning when passing urine, bood in urine, fever and shakes, major discomfort