Increased crp again after one month.

My baby was born at 34+5 days. he is 1month 9days old today.during delivery baby passed meconium which leads to nicu admission. During nicu stay His crp increased gradually to a max value of110. Was discharged after 14days with crp of 3. Yesterday I went for regular checkup and he was given 6week vaccination. Also he appeared bit yellow so doc suggested blood test. Cbc crp and tsb. Today all test were done. Tsb is 10. But crp again rose to 40. Can this increase crp be caused by vaccines given for immunisation at 6week. As a reaction of vaccine baby had a fever to 37.8 for which CALPOL drop was given. Baby has no symptoms of any infection he is playful feeding breast milk well also gaining weight at an average of 33-35 gm per day. Kindly suggest what could be the reason of increased crp and also do I need to regularly monitor crp level.