I dont personally get those feelings but I really dont have bad dp/dr, but it is classic for dp/dr people. I know that right now you just started to experience these feelings and nothing will make it get better. Honestly it will all get better your feelings will start to fade and become less and less bother some. It is really near impossible to think about the fact you will be ok, but if you give it time it will really make a difference.
As for the zoloft I have been on it for several years, when i first had a nervous break down at the age of 14ish. I used to be scared of mad cow disease lol, it set me into quite a horrible spell. Anyway I went to see a shrink they put me on zoloft. My biggest feeling was that it would do nothing and I would be trapped in this anxious state forever. I would go as far and say ZOLOFT IS A MIRACLE DRUG, for me atleast. I know everyone is different but zoloft if you react well to the drug can be highly sucessful.
One note that I would reccomend you do with your zoloft is if you want to go up to 100mg keep the 50 mg your doing then go up 75mg and break a 50 tablet in two. If you still feel affects go 75mg one day 50mg the next day for a while, I noticed that helped me when I weened off. Just play around with it see if it helps. I dont know how much experience you have with A-D's but there are a whole slew of them, if zoloft doesnt work hell there are many out there, more and more coming out each year, so never give up hope.
Oh by the way I went off zoloft the first time before I had another anxiety attack, but when I went back on it for the second time it worked slower. It also had some stronger side effects the first few weeks, if you can hang it out for the first few weeks than the side effects should subside rather nicely for most people.
Best wishes,
orangeaid.