Today I took 2 zyrtac when It says only 1. Bad?

I have horrible spring allergies, I have tried many medications. Like claritin, benadryl, allegra, and zyrtec. Today I took 2 zyrtac when It says only 1. Is that bad? I do not know how much it actually helped, I took them around 11:30 am today, and its 12:30 am right now, it's been 13 hours, and I feel like death. I dont know what to do anymore!