Spearmint tea suddenly unpalatable?

I've been drinking spearmint tea twice a day for a few months, but it's become suddenly unpalatable, like a switch was flipped (previously, I loved the taste). Now, it's like my body is fighting infesting it. I generally believe that our bodies have an ability to self-regulate and I'm probably getting this reaction for a reason: my body has had enough. But I wonder why, since I haven't seen from the research that spearmint becomes an issue with continued usage. Has anyone else experienced a similar change?