Withdrawal then going back on....urgent advice needed

Evening.

I was on Citilipram for about 15 years and tapered then to move onto Sertraline just over a month ago. I moved and was in a good place so decided to stop the 50mg Sertraline. 4 days passed and the first two were fine but the last two I've been gradually getting more dizzy and slightly weard head pains. I went back on them and took one at midday thinking I'd be fine when it kicked I. But 7 hours later I feel so dizzy and weird....I googled which I know not to do and now am so worried. I'm going to take one in the morning as well but wanted to know if the body is just wondering what's going on so taking time to think again or of it's something worse?