A few considerations...
a) You've got the 3rd/9th axis intercepted - 3rd/9th is the mental axis, with the 3rd being the logical mind and the 9th the abstract, philosophical mind. Intercepted houses are said to point to areas of special focus, things we need to work through to further ourselves
b) You've got Pluto, ruler of psychology and self-observation, among other things, rising tight with the ascendant, at the final (hot) degree of Libra (balancing) -- some balancing of the self's projection (ascendant) is indicated, and Pluto plays a big role in your persona.
c) You've got your Sun smack between (midpoint) Mercury/Venus; This can indicate some pull between wanting to be logical and analyzing (Mercury) and abstract and creative (Venus). This midpoint in and of itself says nothing of any sort of trouble, but the pull and blending of fairly different energies focused by your Sun (conscious) could be a contributing factor. Mercury also sits tightly between Venus and Jupiter, two quite abstract planets. Mercury/Venus also form a novile aspect (40 degree, 9th harmonic) further linking the two.
d) Your Mercury is Retrograde, and before the Sun (by zodiac degree), a phase Michael Meyer terms "Promethian Retrograde", indicating a mind that likes to go against the social norms and conventions, in a rebellious fashion. This is a placement of serious thinkers and philosophers, and we're all a little crazy in our own special ways; not that there's anything wrong with that
This is also the beginning of Mercury's 4-fold cycle, indicating the new building of the mental facilities created anew. Challenges you face will contribute to the building of Mercury, and are likely engineered purposely for your personal development. More on the Promethian Mercury, a placement I too have:
http://www.khaldea.com/planets/merc_px.shtml
e) Mercury in tight quintile to Saturn (in fact the closest aspect in your chart counting the planets/nodes) - Mercury is the mind, Saturn is structuring and the quintile (5th harmonic, 72 deg) aspect is strongly associated with unique and highly personalized ways of expressing oneself, much as is the 5th house, and the 5th sign Leo. So, the structures you build in your mind are expressive and unique, and when it comes to ways of thinking, psychology unfortunately says that any mental structures that don't meet rigid expected guidelines are issues... The field makes little deviation for the uniqueness of individuals, and how some "disorders" are actually part of a deeper karmic healing process within the native.
In the end, I'm sure we both qualify for a hoard of psychological disorders. I have the unfortunate reality of coming from a family of psychologists, and can easily say that conventional western psychology, as taught by the universities, is reductive and limited, and it insults the potential of man's ability, reducing a vast majority of our ways to issues created by either chemical imbalances or unresolved childhood difficulties. Sure, some shrinks get past the reductive nature and limited scope of their field, but you'll find these fine folks generally employ many more methods in their practice beyond typical dry psychology as taught in the universities, including astrology and other metaphysical arts. They call themselves psychologists (and got the degree) so they can help people while insurance pays for it, something hard to do without holding a psychological degree these days.
It's also not surprising to see someone with Neptune (drugs, etc) on the 3rd house cusp (the mind) enjoy mind altering substances. THC is actually an excellent dopamine-system balancer and far less harmful than some other substances, assuming it's not used in excess which can lead to lung difficulties given prolonged usage, a normal side effect of any smoked substance. Many people find it a suitable replacement for the various psychotropics that greedy drug companies are pushing. I'm all for natural medication over lab-brewed chemicals.
Addition: Your Mercury is not only in tight aspect to Saturn, but placed in Capricorn: Could rigidity place a role in what you may face? Saturn/Capricorn represents a rigid energy that likes to hang on to past tendencies.
The sabian symbol for the 17th degree of Capricorn, your Mercury degree, is also most interesting:
287 (Cap 17°)
REPRESSED WOMAN FINDS A PSYCHOLOGICAL RELEASE IN NUDISM Escape from bondage to social inhibitions. Readjustment of relation of spirit to body. Self-purification. Self-confrontation.
___*When positive, the degree is a highly effective dramatization of the basic characteristics and potentials of self, and when negative, furtiveness or eccentricity.