Hi,
You seem to be having honeymoon cystitis.It is actually a form of urethritis.Abstain from intercourse for a few days,take plenty of fluids and take some OTC analgesics like ibuprofen or diclofenac.Also take pyridium for 2-3 days(it stains the urine orange) and sit in warm non soapy water.Also consult a doctor for antibiotics prescription if the symptoms persist.In future also,urinate immediately after intercourse to flush out the bacteria and ask your partner to indulge in plenty of foreplay or use lubricant jellies.
Regarding the inter menstrual bleeding, it can be due to vaginal trauma but if it happens again then get it examined from a gynecologist.
I sincerely hope this information helps. Take care.