It's been 34 days since my last period?

I'm 18, not sexually active, and my periods are always 18-20 days apart. I haven't had any health problems or out of the ordinary symptoms, but I just checked the calendar and it says it's been 34 days. I did change my diet two weeks ago after losing a significant amount of weight over the past year, since I was eating completely clean, and only fruits and veggies to now eating some pasta and including carbs and lots of protein. I doubt that it would have this much of an impact on my period though. I'm just a little worried and am not sure what's going on. Does anyone have any ideas?
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+1 y
I've been extremely irritable the past few days, so I'm not sure if it's right around the corner or just because I haven't gotten it and my hormones are acting up or what. I figured I would ask though, just in case because I don't want to go to the doctor and have to pay a bill if it's not a serious issue or will be here tomorrow.
It's been 34 days since my last period?
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