Vaginal bleeding accompanied by urinary tract infection, what should I do?

Patient's question:

Hello Dr. Liu, I am 20 years old. After my boyfriend inserted his finger into my vagina (quite roughly), I walked quickly for about 20 minutes, and then I experienced bleeding from my vagina accompanied by a sense of urination. The blood was bright red. After one day, I developed lower back pain, but the pain subsided after another day. Could you please tell me what might be the cause of this and what I should do? Thank you

Doctor's answer:

Still, it's best to go to the hospital for a gynecological examination as soon as possible!