ppd/ppa

I think I may have one or both. I'm almost 4 months postpartum and have been feeling great up until the last couple weeks. No matter how much sleep I get, I'm still tired, irritable, sometimes sad for no reason, occasionally feel overwhelmed, and have these terrible intrusive thoughts. Do I see my midwife, primary dr, or therapist? If you have ever been on medication for either ppd or ppa, do you feel it helped? When you went off the medication were you still feeling good like you did on it? I'm afraid if I start taking medication that when I have to come off it I won't be better. Thanks for any and all advice.