Do I have a mild case of tubular breasts? I'm 21 years old. (Photos)

Hello and thank you for your question.   You appear to have mild tuberous breasts, in addtion to ptosis and asymmetry.  You are a great candidate
for a breast augmentation.  The size, profile, and shape of the
implant is based on your desired breast size/shape, your chest wall
measurements, and soft tissue quality.  This decision should
be based on a detailed discussion with equal input from both you
and your surgeon.   Make sure you
specifically look at before and after pictures of real patients who have
had this surgery performed by your surgeon and evaluate their results.   The most important aspect is to find a
surgeon you are comfortable with. I recommend that you seek consultation with a
qualified board-certified plastic surgeon who can evaluate you in person.
Best wishes and good luck.
Richard G. Reish, M.D.
Harvard-trained plastic surgeon

If you are unhappy with the shape of your breasts there are many options available to you these days to correct them.  The diagnosis is less important than the fact that you are unhappy with how they look and it is important for you to know this can be improved.  Based on your pictures there does appear to be some constriction of the lower part of the breast - this could be described as a mild case of tuberous breasts.  Correction usually involves placing implants and making some adjustments to the breast tissue and often nipple position.