Watery discharge from ear comes when there is an infection of ear. Kindly try to keep that ear dry I mean avoid water entering into the ear during a bath or swimming which will aggravate the ear problem. Use cotton plug smeared with Vaseline to keep in the ear and take bath.
You need to start on a course of antibiotics for control of infection before starting, get the culture sensitivity of ear discharge done. This helps in knowing the drugs you are likely to respond.
For the pain you can take paracetamol with aceclo combination tablet twice a day for three days. Avoid using ear drops. Oral decongestant like levocitrizen to be taken in night after food for a week. Once you have the antibiotics for a week ears dry, can get a ent consultation to asses the ear drum and further management.