Fever blisters bad outbreak help!!!!

I've been getting them since I was a little kid, they used to be so bad but now not so much. I noticed the signs last night and instantly filled my prescription for acyclovir and took my dosage for today, but it's getting worse. I also put tea tree oil on them. I really thought the acyclovir would prevent it since I took it before the bumps popped up but no here they are. What do I do?! It's so uncomfortable