Possible leak in Fermenter

I think the rubber grommet on the lid of my bucket might not be air tight. I plan on keeping it in the primary for 3 weeks. Should I relplace the lid on the bucket? If so should I replace it now or wait a few days since it just started fermenting?

The reason I don't think it is air tight is because it is a new lid and I noticed at the last minute that the grommet is a little deformed on one side and does not sit flush against the lid. I pitched a healthy yeast starter on saturday night but am not getting activity in my air lock unless I flick it. They it will bubble for a minute or two then stop.

 

Yesterday I was about to change the lid since the homebrew store is closed on Mondays. I found a video on youtube where a guy had no airlock activity because the water level was barely below the small slits on the inside piece of airlock. I got home added a little more water and boom problem solved. All shame of feeling like an idiot was completely washed away by the sweet sound of a bubbling fermenter. Thanks for trying to help out a true noob.