I doubt that this is a side effect of Celexa since it could be serious but is not listed below, so you should talk to your doctor or a clinic to see if something else is wrong. The link below lists the Celexa help line, but I doubt they are open before Tuesday.
If you're only 22 it's unlikely to be the most common cause of this in men, which is an enlarged prostate. I have this all the time thanks to a wonderful (joke) surgeon and it's no fun, but I'm 64. If this started only when you started taking the Celexa, you didn't have any urination problems before 5 days ago, while this isn't a common symptom, individuals do suffer quite individually with the side effects of altering the way your brain sends signals to the rest of your body. I've never seen or heard of this one and I've been on Celexa for several years, but what Celexa and its newer relative Lexapro do have as common side effects are pressures, such as on the head. Maybe you're getting that pressure in that area. Easiest way to find out is to just stop taking it -- after only 5 days there will be no withdrawal and if the problem stops then you'll know for certain it was the Celexa. It's possible if it is a very unusual side effect it might go away with time, but again, the only way you'll know it's the drug is to stop it and you can only do that easily when you first start it -- after that, you'll have to taper off slowly to prevent withdrawal. But even if you do that or don't do that, I'd see my doc and see if there's any prostate issues going on just to be sure. Sometimes young men do get issues, although they tend to be temporary, especially if they take steroids.