I've regretted all three times I got roped back into going back on the pill by my doc.
I like Christiane Northrup's take on it that gynecologists are essentially trained that women have a "birth control pill deficiency".
My symptoms in the first month (even on a mini pill):
Loss of intuition (it felt like I was missing my peripheral vision, and couldn't tell when someone was walking up to me from behind if I didn't hear the footsteps). I found this to be both spooky and dangerous feeling.
Chronic low level anger that I couldn't seem to dissipate without a ton of cardio exercise, like hours on an exercise bike or 5-7 mile walks, and even then it would creep back within a day.
Longer-term symptoms:
Inability to orgasm
Being drawn to a partner whom I was no longer attracted to when I went off of the pill
Weight gain
Hypothyroidism
Depression
And...I suspect the triggering of my PCOS (I know it is prescribed to deal with symptoms in people who already have it, but my symptoms all started after I went off of it after the 2 continuous years of the initial use).
I did all of my hormonal birth control use years before finding paleo, so I'm sorry I am unable to answer the rest of your question.