Effexor to Zoloft ?

Need some advice got put on Effexor In March following sudden panick attack and anxiety. I was stuck in flight or fight and couldn’t sleep, had horrible dpdr, and have never had anxiety like this before. I was put on Effexor as my first med. After 5 months I feel like I’m finally getting back my life. I have therapy. I’m on 75 mg. My psychiatrist no longer works at the clinic and I have a new one. given my fear of the medicatio, ocd, and worsting anxiety on my period. The new psychiatrist wants to try switching me to Zoloft. I am scared to regress and to mess anything up. Will all the progress be reversed? Should I not let the fear of withdrawals be the reason I would want to switch? has anyone switched to Zoloft from Effexor after a few months ?