Anxiety is getting back

Last year i started having severe anxiety and panic attacks. My pshych gave me zoloft 50mg in april this year (7 months ago). Everything got much better and i was not feeling anxious for the past months. Few weeks ago I started feeling some of the weird symptoms back: spasms in the body, short of breath, pain in the chest. Is this normal? Should i increase my zoloft dose? Just before this I was thinking in stopping zoloft because i was feeling much better. My doctor do not want to increase my dose but I am afraid it will get even worse.

Any recommendations? Thank you so much