Hey Hylke! I can sympathize with your situation, I am 17 years old and I've been playing for probably last 6 months on chess.com and reading up on chess books. Now mind you, 1400 on chess.com is enough to beat most children unless they are exceptionally strong in the first place. I joined a chess club last month and I have really loved it. The people are really accepting of new-comers since it adds some excitement to pairings and the club is similar to yours in that the majority of the people are over 50 including two players with FIDE ratings over 2200. They truly enjoy seeing younger faces (yes 17 or 19 is quite young in their view 
) and after every game they will offer to go over the game and help you improve. It's a great improvement tool and you should have lots of fun. For reference: In my first chess club tournament I beat a 1500, tied a 1480, and lost to a 1790 and 2070. Overall a pretty good month for me, and great fun!
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same thing, 21, only 1300.
I am 16 and joined a chess club a few months ago (when I was 15) and they were very welcoming. You'll learn a lot if you join a club, so I say do it! 
Hey Hylke. I am 21 and have chess.com around 1400, and i was thinking the exact same as you. I have not joined a chess Club yet, but i am planning on doing it. Everybody i have asked about this question has told me the same as RoyalFlush1991 told you. I sent a mail to the The manager of my future club and he told me that age and rating was no problem, as they had players with all kinds of ratings, and i was told that the better players often helped the noobes.
Do you really think anyone on the chess club will care of what playing strength you are? Just join & have fun.
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