Hello and thank you for consulting Just Answer,
First I want to make sure you understand that we cannot diagnose you or treat you on this website. However, we can give you information to help you make your decision.
The symptoms you describe may be indicators of Bipolar Illness. However, it is also possible that you suffer from Major Depressive Disorder
or another mood disorder (there are several). It takes a face-to-face evaluation by a psychiatrist to be sure. The sooner the illness is treated the better...and the better prognosis for the future. So please do not hesitate to make an appointment. It may take several weeks to get an appointment.
Here is a website that you can see pictures and descriptions of some psychiatrists in your area. http://psychiatrists.psychologytoday.com/rms/
Concerning the medication....there are side effects but you need to weigh the benefits and the side effects. If your symptoms are interfering with your life and it is getting worse, then it might be worth the initial side effects (stomach aches, dizziness
, headaches). They usually go away after about 4 weeks.
Along with medication, therapy is recommended. It is interesting that you are trying to change your negative thoughts because that is exactly what is taught in therapy called Cognitive Behavioral Therapy. To find a therapist to here: http://therapists.psychologytoday.com/rms/prof_search.php
It is ultimately your decision, of course, but making the initial visit for a diagnosis does not mean you must try medication. You can find out for sure which diagnosis applies and ask doctor questions about options for treatment. You can also try therapy first.
I hope this helps you take the first step....because early treatment means better chance for relieving symptoms.