Hey mama, it really does sound like it could be your mucus plug, especially at 39 weeks, that timing makes sense! The fact na parang mucus talaga siya and odorless is a good sign na it's likely that, hindi infection. Since you've already checked with your OB, that's the best move; just keep an eye out para sa regular contractions or any bleeding, at follow their instructions on when to go to the ER. Good luck, you're almost there!