Pristiq to Zoloft = depression

Switched from Pristiq back to zoloft. I was having dizziness and other side effects, so I wanted to try switching back to zoloft which I was previously o

for GAD. My doctor had me taper down from 50 mg of Pristiq to 25. I felt good for a week and then bacame depressed for about 3 days, then it lifted. About a week ago, I quit the 25 mg and began taking 50 mg of zoloft. Again, I felt great for a week , but the last few days i have been really depressed. I have only been off pristiq for about 10 days and in zoloft for 10 days. Do you think the depression could be my brain adusting to the changes in medication. I'm 5 months off Ativan. Never really dealt with depression, just generalized anxiety, but since my taper and jump I have been dealing with depression much, much more. It seems to be a roller coaster ride. Ill feel great for a while and then depression hits again. Im so tired and confused. Should I be patient and wait 6-8 weeks  and see if the zoloft begins to work? Thanks for any help you can give me.

Fp

You try exercising can you exercise walking two or 3 miles a day helps with depression

I definitely need to add  excercise to my regimen.