I get lung infections off and on, i used to cough n left shoulder blade would ache , it's hurting but no cough do you think it's infection again?

Doubtful: Pain in the scapula area can be related to muscular strain/stress unrelated to coughing. If there is no cough, fever, chills etc it is not likely infection. Have you done a new activity, slept in a different bed or been stressed over something recently. Any may cause aching there also. If simple analgesics, local heat compresses, stretching, massage don't help get to a doctor for examination.