Is it the Zep or is it just my Body

I just took my week six shot this past Monday, and so far everything has been going fine. I’m down thirty pounds through a mix of diet, exercise, and the shot. I haven’t really had any side affects since starting. But this past Monday when I took my shot I spent the whole day super nauseous to where I couldn’t eat or anything and fought back vomiting all day long. So I ended up sleeping away most of the day Monday. Tuesday it seemed to get better but I still had some abdominal pain and I felt like I needed to have a bowel movement which everytime I would try to go nothing would come out. Now Wednesday is the same thing. Still having abdominal pain and still feeling like I need to have a bowel movement but nothing is coming out. I haven’t really been able to eat this week so far because of the nausea and pain. Has anyone else experienced this before? Is it just me or could it be the Zep? I haven’t changed dosage or anything so I’m still on the starter 2.5. Any tips or tricks? I’ve been drinking over 100oz of water a day to try and combat constipation and these issues .