Can a Infected tooth swell your lymph nodes in chest and neck? I needed a root canal for a while and the tooth was infected and my nodes are swollen.

Of course. A tooth infection won't go away without treatment and the infection may spread to your lymph nodes, cheeks, sinus and to other areas of your head and neck. OTC pain medications such as NSAIDs, Tylenol (acetaminophen) or prescribe antibiotics can all reduce the symptoms, but none of these treats the cause. Visit a dentist ASAP for definitive diagnosis and treatment.
Yes. Yes, see MD ASAP for antibiotics. Get tooth treated ASAP.
Infected node. Anything is possible. Your lymph nodes act as sieves in your lymphatic system. If the tooth is badly infected and the body has been fighting the infection for some time, the lymph nodes may be swollen and tender by doing their job; don't delay the treatment--get the root canal or get the tooth extracted. You are only hurting yourself.