Greetings.
There's more to it than just who is and is not shallow. First of all it matters what you like. If you feel and understand on what you react more, there is nothing and nobody that can or should perssuase you to do the opposite. For example, regardless of the persons intelligence or wisdom, if his physical predispositions do not match your requierments, you shouldn't go in for him. Likewise, if you get aroused when the person debates the balance of nature and humanly paradox within it but generally appears ugly (for each its own), then you should not care about what may other say for the choice you picked up. It's you and him (or her through the text) that matters, and it will and should always "you and him" matter more than "you and them".
Second, there's a fact that tells us people can't really change themselves. If you're being "shallow", it theoretically means other believe you're shallow but in the same time - you will and can find people who will consider your drop off absolutely logical. We are a complex beings of nature and there are billion psychological aspects in each of us. Therefore, if it is not a life-important issue, who will you end up with, you should be going by the way you like because ->
Third, once you do encounter someone for whom you'll believe to be the sanctuary of yourself you will feel and understand it completely and you will not care what kind of haircut he did. It's a point in life that simply happens.
In my opinion, you should just do what you feel like, specially since you're not a 55 year old whore but a young girl/woman, but learn not to hurt people - simply - include some common sense and end everything in peace. It will make you and them feel better, and you are yet not obligated to each of them or to follow anykind of routine.
Hope I helped.