I LOVE and hate the b****

Okay, I have had a thyroid issue for years, and my weight fluctuates soooo bad, like I'll lose 10 lbs, then gain 15 within a week/ week and a half, lose 5, gain 6, but I've always had consistent periods... until this past year. I've been gaining more weight and losing it within a small amount of time, and my period has just .. I don't even know, it's like she had a mind of her own now, and it has become so irrigular that it makes me anxious. I used to get it on the 13th to the 18th of every month, I could even pin down what time of day it would be here. Now, it's doing this skip two months, last a week, skip three months, last 3 days. I was getting kind of nervous this past time because it had been 3 months since my last period... I am currently sitting in my bathroom now celebrating because it's finally here, but I'm very moody and emotional right now.

Should I probably go to the doctor to see if there is another reason why I'm so irrigular?