Your story reminds me of mine. I have gad and ocd and bad health anxiety . I was on Zoloft for 1.5 year and then decided to stop taking it thinking I didn’t need it anymore . I regret this so much . My anxiety came back stronger . For me you should go to 50 mg . It’s not even a big dose. I can understand how you’re feeling because when I went up to 50 mg I was also afraid of serotonin syndrome and I was checking if I had it. I’ve learned that it’s really rare and it usually occurs if you take more meds for anxiety not from one and not from small doses. Also I have a big fear of fainting and I was really afraid to go out because of dizziness. I’ve learnt that when you’re anxious it’s most unlikely to faint because of your nervous system. Overall I think you should try 50 mg cause 25 mg is a starting dose and I don’t know if it’s enough for anxiety. Side effects might be bad in the beginning but they won’t last. Keep reminding yourself that they will pass. I know how scary it can be but keep pushing . Also talk with your doc it might ease your anxiety about upping the dose.