if you are on a budget don't eventhink about discus. They are a lot of money need to be kept in groups and need a 60 gal bigger is better.
38 gal is too small for a severum you might get away with a 55 gal for one for awhile. A full grown severum will need a 70 gal they are big fish. Look for a used 55 gal on eBay or craigslist if you are in the US.
There are lots of awesome dwarf cichlids you could look into instead of the large severum. Keyhole, rams, dwarf flag cichlid, smiling acara,Apistogramma ( many differant kinds of these guys ). Mid size cichlids firemouth, convicts, blue acara, just to name a few.