I am on antibiotics for a root canal that is infected, it still swells and is uncomfortacle when I lay down at night. I had it exrayed , it wasn't cracked looked good, but is it bad since it won't get better at night. I have a temporary crown on it and when it swells is hits my bottom teeth is that making it inflamed?Help I want to keep my tooth. How long can I wait before it should be pulled to make sure it needs to be. I am finished with the antobiotics in four days. Thanks

Sounds like it might be abscessed and the antibiotics should help.
Check with the dentist/doctor to see if it would be okay to take Tylenol or if they will give you a prescription for pain or if you need to go in and be checked again.
When you are done with the antibiotics it would be good to take probiotics or eat yogurt to replace the good bacteria.

Take some Ibuprofen (Advil) as well as your antibiotics. Advil will work as an anti-inflammatory which should help when you lie down. Take 1-2 tablets every 4 hours (as long as you aren't allergic to Ibuprofen).

An x-ray won't usually show a crack. Did the x-ray show an infection at the tip of the root?

How long ago was the root canal done? Was it done on a molar, bicuspid or front tooth? If it was done on anything but a front tooth there may be an extra "auxillary" canal that is causing the tooth to remain infected. You may want to see an endodontist (a dentist who specializes in root canals) before you decide whether to have the tooth removed.

Whatever you do, don't have your temporary crown replaced with the permanent one until the infection is taken care of.