There is a weird smell in my apartment, should I be concerned? what is the best course of action here?
If you have noticed an odd odor in your apartment and it persists despite efforts to remove it, there could be a number of potential causes. Here are some steps you can take to try and identify the source:

1. Check the AC or heating system: Make sure that the AC or heating system is functioning properly and not emitting any odors. If necessary, consider upgrading or repairing the unit.
2. Vacuum the carpet: Use a vacuum cleaner with a HEPA filter to clean the carpets thoroughly. This will help eliminate particles and dirt that may be contributing to the smell.
3. Scrub the walls and floors: Use a mild cleaning product like muriatic acid to gently wipe down surfaces such as the walls and flooring. Be careful not to get the solution on light-colored furniture or upholstered items.
4. Clean out the refrigerator: You may notice an unpleasant odor coming from the refrigerator's cooling mechanism. Try running the ice maker for several hours to clear out any debris or buildup that may be causing the problem.
5. Change the air freshener: Sometimes, old air fresheners can emit a strong odor that lingers in the room. Consider replacing them with new ones made specifically for eliminating pet smells.
6. Seek professional advice: If none of these measures work and the smell continues to persist, it might be time to contact a professional HVAC contractor to diagnose and fix the issue. They can assess the situation and provide recommendations based on their expertise.