Hey, I never really smoked before but yesterday I had a few and now I have some white spots on my throat. Strep throat? Mononucleosis? Infection?

Likely an infection. Most sore throats are caused by viruses and do not require antibiotics. Rest. Drink lots of fluids. Gargle with warm salt water 4 x/day. Take Tylenol (acetaminophen) up to 4 times/day if you have a fever or feel uncomfortable. If your symptoms do not improve in 4-5 days you should have a strep test. If strep throat is not treated with antibiotics, it can lead to serious consequences. DON'T SMOKE!