Yes, it is possible, many people with Bipolar that has not yet been DXed are usually seen by pdocs/therapists when they are depressed, when they are hypomanic (mild mania) or even manic, most feel good, energies flowing so they do not feel a need to see a professional.
I would see a pdoc and get an evaluation to either rule out your former DX or confirm what the true problem is, so if you end up needing meds you can get the proper ones.
Yes, people can have more than one disorder, according to the pdocs I have seen and/or spoken with.
Just try to hang in there and seek professional help.
Feel free to always drop by and talk to us.
Take care now,
DE

In giving advice seek to help, not please your friend
SOLON