How can i tell if i'm experiencing manic depression or post traumatic stress?

See a therapist: A licensed therapist. Psychologist or psychiatrist can make that distinction.

Some people suffer: From both. They have some sxs in common. A bipolar can have increased energy (mania or hypomania) & ptsd can present with hyperarousal/ fight or flight rxn. Both can present with depression. Aggression, agitation and irritability can be common to both. Sleep is usually impacted in both. It is best to have mental health provider (diagnostician) evaluate (& it may take more than 1 session).

Need too see a doc: If u are the one experiencing the symptoms, it would be very difficult for u to make the distinction, partly because both impair the functioning of the only instrument you have to help u make the distinction - your brain/mind. Dr. Fowler has already pointed the similarities and differences between the 2 and the fact that they can occur together in the same person. Best to get a psych eval asap.