If the problem started soon after taking the medication, it is very likely a side effect of the medication.
There are so may anti-depressant choices and patients tend not to have the same side effects to each of them, even with in the same class of medications. The good news is, if it is a side effect, the problem will be completely resolved once the medication is stopped and eliminated from your system. If you are able to tolerate this (with your level of symptoms), i find it the best practice to stop the medication and make sure this is the problem and that the client is better before starting another medication. So that we are not confusing the situation further.
If this is not the cause, then yes, the treatment is different. In addition, the medication can always be restarted.