I was diagnosed with gerd. Been taking omeprazole daily for years. It helps, but the package says take only for two weeks. Is daily use ok?

Usually. Daily ppi use for gerd should be reserved for those that have be or worse enough symptoms to warrant its daily use. The side effect profile is very good, however more evidence is being accumulated regarding potential side effects with long term use. You want to slowly titrate off and see what happens. Discuss with your doctor as you may need an egd.
Yes. Daily ppi use is ok but should be monitored by a gastroenterologist. An egd may also be necessary to evaluate for gastritis, h pylori, and barrett's esophagus.