Uy, please check with your OB right away, kahit walang pain, it's best to get it checked out especially when you're this far along na! Sa 36 weeks, any changes deserve a quick call to your doctor or a visit, para masiguro na lahat okay sa baby at sa'yo. One of my mum friends had something similar and her doctor just did a quick check, turned out fine, pero she was glad she didn't wait. Don't worry too much, but don't wait din, better safe than sorry, 'di ba?