Can't figure it out

Had my 4th Remicade infusion yesterday morning. Once I got home, I was very bloated and had abdominal pain . Slept for less than 2 hrs and woke up w severe abdominal pain and the need to have a bm. Couldn't pass except a little and the abdominal pain was severer. Called my GI as pain was escalating. After 2 hrs, his secretary called back and told me he said he has to see you tomorrow, take your meds as regular and he won't do anything now.
Today I was dizzy and drowsy like what happened after the first infusion. If I still can recall, I had severe abdominal pain and d (10 times+), drowsiness and dizziness that lasted for 5 days, 2 days after the first infusion . I also had the same scenario with my GI where I called hime and he asked to see me the following day.
However, these post dose symptoms did not happen w either the 2nd or the 3rd dose.
I took the dose this time after 7 weeks. But symptoms returned w vengeance and even severer than prior to taking remicade. Could it be that in doses 2 and 3 which are part of the loading doses I had the drug still in my body? And by week 6, I totally ran out of it? Does it mean that I need to take the dose earlier may be in week 6 or are things going to be different especially that this is the first dose after the loading doses have been finished?