11 days after tummy tuck, I have thin reddish odorless weeping from the incision. It's increases daily. Is this to be expected?

As you mentioned that the drainage is increasing daily, I encourage you to visit with your surgeon for an evaluation. Your surgeon will rule out seroma formation or other concerns. Typically these concerns can be addressed in the office.

Dear chenos,it is hard to tell without an examination. I would suggest you to consult your plastic surgeon. Only after a thorough examination you will get more information and recommendations.Daniel Barrett, MD, MHA, MS 
Certified, American Board of Plastic Surgery  
Member, Am. Society of Plastic Surgery

It sounds as if this may be some seroma fluid.  In general, it is better out than in!  However you should get checked by your surgeon.  I would also recommend continuing to wear your compression, especially when up & about during the day.  All the best