How To Treat Pain In Thoracic Cavity Due To Fluid Build Up?

I had CDH surgery on a Morgangi Hernia which had all my greater omentum in my thoracic cavity on jan16. The surgery was done laproscopic at Mayo Clinic by a thoracic MD. I went for my followup and the ct showed fluid in my thoracic cavity. The DR said it would absorb into my body and what didn t would scar off and wouldn t cause any problems. He said the pocket was the size of a fist. Is this normal and should I look into this more? He said he wasn t going after it nor ordering another scan although he said it was a little larger then he would have thought. The estimated 18 lbs was pulled down from the thoracic cavity and the repair to my diaphragm was the size of a fist with mesh repair. I liked the surgeon but feel uneasy now worried and not a feeling of peace. I still have some pain when I eat and pressure behind my breast bone, he said takes time to heal. How long until the pocket absorbs and should I look into it more