Xray Paranasal sinuses can give only limited information about sinuses..
you could have had an acute episode if sinusitis which can be seen as left maxillary sinusitis. it may get completely resolved with nasal decongestants and antibiotics. you have a deviated nasal septum..which if symptomatic may require surgical correction.
Next Steps
hydrate yourself well.
Health Tips
consult ENT if symptoms don't resolve completely. get a CT PNS for chronic Rhinosinusitis..which can confirm diagnosis. do it after adequate treatment with topical nasal steroids.