People with experoence with antidepressants, do i really need to take one, and should i stop the research stud?

study i'm on where i am taking pills, but i dont know if they are placebos or the actual investigational medicine. i experienced some overwhelming feelings that felt different from my usual sad or overwhelming feelings. it wasnt the most intense or overwhelming i've ever had, but it felt very different and it scared me, becuase it felt abnormal for me. i called the place that does the research study and they talked to me gave me advice said that it doesnt sound like something from the drug, but the drug is investigational. they aggreed to see me soon, so i can talk to the doctor. my question is i dont know if i should stop the study or if the symptoms are really just the depression and maybe im taking the placebo, or the medicine may not even be having an effect. i took lexapro in the past and that had no effect on me so i know its possible, and the sypmtoms of muscle weakness and overwhelming feelings, even a panic attack are symptoms i have had without medication, but the muscle weakness was from me crying so hard, and i understood why i was crying and why it caused my overwhleming sadness. i have been thinking intensely and overthinking and have had a lot of mental activity which i have had in the past but recently it increased.i have been taking the "medicine" for 3 weeks. i know the dosage is supposed to increase but i dont know by how much. how do i know whats normal depression and what is exacerbated by antidepressants? i'm afraid of doing irreperable harm, but if this is really just the depression and not the medication i need to find out so i can get adequate help. what should i do? thanks in advance for the help and for taking the time to read this. i feel better at the moment and i feel like i can deal with this happening again, but for how long what if it gets worse?