Breathing pain

I've been having a problem for the past few months where when I breathe in deep I have pain that feels like it's towards my back. It gets a lot worse when I lay down especially on my back almost a sharper pain. Thought it could be a pulled muscle but I didn't know what from but now it seems to be getting no better after months of it going on. The pain almost feels like its at my back towards the bottom of my ribs.

[National Jewish Health]

As you describe your pain it does suggest that it is muscular.  It could be aggravated by the position you assume in sleep.  If it continues to get better, be patient.  If it gets at all worse, you should see your doctor and, at a minimum, have a good exam and chest x-ray.