In my experience, you need to get it repaired and I would go the professional route. They put a vacuum pump on it to draw the adhesive into the cracks as far as possible which results in a much more durable repair. At least where I live, getting this done is cheap, maybe $30 or $40 total.
If you don't fix it, you may be fine or it might get worse. I was riding with someone that had a rock chip on their windshield for years with no problems and then with a loud pop, a crack went clear across the lower part of their windshield. I have gotten chips on my 18 year old car twice and I still have the original windshield.
This may be obvious to most but I have met people who didn't know so I always tell someone that when you get a crack or rock chip fixed, it doesn't disappear and become invisible. You will still see the divot or crack. In your case it sounds like it isn't in the main area of vision so shouldn't be a problem.