Borrelia does not regrow that fast, but bartonella can. It's also possible that you're having a delayed herx if you've been taking anti-inflammatories, where your immune system will react more strongly when the anti-inflammatory effect wears off.
I would also strongly suggest not throwing random antibiotics or herbals at bartonella, because of the tendency to wake up dormant bartonella. If you're going to attack bartonella, you need to kill it. If you disturb the dormant bart but don't kill it, it will just become more active and make things worse.
The problem is that bartonella needs to take iron and heme from red blood cells. When subject to stress, it needs to do this more frequently. This research explains it pretty well:
https://www.ncbi.nlm.nih.gov/pmc/articles/pmc3365110/https://www.ncbi.nlm.nih.gov/pmc/articles/pmc3483173/So if you hit bartonella with the wrong anti-microbials, it will use up the iron and start attacking your red blood cells to get more.
If you're trying to kill bartonella, you'd better make sure it's dead, or you're going to have problems when it wakes up and gets angry.