You can try. I would hire a good local attorney and have him or her file a motion to exclude the statement or suppress your statement on grounds that you and the attorney discuss. If you were not competent and did not understand what you were doing at the time you may have grounds to keep the statement out of evidence. Bring your medical history and any medications you take to the meeting with your attorney and discuss the total situation with him or her.
You could recant the statement but It would be advisable to consult with experienced criminal defense counsel first. There could be benefits of recanting or perhaps not. The fact that you were possibly manic at the time the statement was given could help with your defense. Don’t go this alone! Speak with Counsel ASAP.
This response does not create an attorney / client relationship and should not be relied upon to make decisions in any case. It does not substitute for hiring your own attorney and consulting with him or her to provide in depth legal advice.
It is difficult to give an accurate evaluation of your case based on the limited information provided. It is best to contact an experience attorney who can evaluate all the facts and help determine your next best course of action.