It partly depends on the champion you play, but normally ,while ganking (unless enemy is reckless) will hurt your progress it will help laners a LOT, so it will increase your win chances. Some of when to gank and when to not comes with experience, but don't give up on it. Though if there are no good ganks, just farming is OK for most junglers, doing this all games is not what you want to do.
Jungling is unique in that it has a thing called "catchup experience" -- if you fall behind in levels, you will get MORE experience from your camps, so don't worry about falling behind a couple of levels, if by doing so you benefit your laners enough.
Not to mention with new scuttle, having a stronger laner increases chances they'll be able to help contest it, or in general apply enough pressure for you to have a better run of the map.
One more thing as a junlger -- more often than in other roles (except possibly sup), there will be toxicity directed at you. Ignore it, if someone blames you without being constructive, chances are the problem is them, not you.