Hi there,
I would recommend that you not do any insight practices for now, make a vow not to make progress for now, and instead focus on stabilizing through nutrition/light easy basic mindfulness meditation/stopping recreational drug use. Insight practices can then be resumed when you have been stabilized for some period of time. Given this sort of history, I would caution against immediately going on any extended official retreats as well (even after you have stabilized for some significant period of time).
If you see a psychiatrist, they are very likely going to put you on some anti-manic-depressive type drugs as well as give you a somewhat "meaningless" diagnostic label which will then also get thrown at you by your therapist. If this label persists the mind will then try to struggle with it in extreme terms of either denying it or totally embracing it. Though these may be helpful for now, there are some issues that come up with this psychological struggle as well as with the medications if you wish to continue insight later (as well as causing a lot of unforeseen issues if you choose not to continue insight later). The drugs will help with the symptoms, but are extremely difficult to come off without precipitating intense withdrawal symptoms and extreme "episodes," so much so that I recommend not going off them (once you start) at all until you are very highly realized.
I have written more extensively (with links about information on medications/vitmains) on the topic of manic-depression/mental illness and dharma practice in this post:
http://www.dharmaoverground.org/web/guest/discussion/-/message_boards/message/3373753I would not at all recommend that you go anywhere past the "training the puppy phase" of which I wrote about in that post.
EDIT: It could be argued that if you keep practicing then you can "get stream-entry" and then everything may be okay. However, I would be on the cautious side as "getting stream-entry" isn't necessarily a cure-all as there will be intense review cycles afterward as well as the inevitable start of 2nd path which could possibly lead to even worse symptoms/horrible situations than this if you don't practice calming these sorts of things now.