I'm sure there are tons of programs that do medsurg and psych in third semester but where do you go to school at? I went to American River College and we did ob and peds in second as well as psych in third.
Speaking in general, I felt like psych was easier compared to OB and peds. Some people found psych test questions to be a little different than others... It's all about maintaining the milieu and therapeutic communication skills, all the different disorders and what meds are prescribed for them. Psych clinicals were interesting. Attending lots of group sessions, vital signs, assessments, charting their mood, affect, thought content, etc. What I thought was most interesting in psych was how well ECT therapy worked. Didn't even know they still performed that on patients until then.
2nd semester with all the three subjects crammed into one was what made it, what I thought, the most difficult semester. I was definitely the most sleep deprived and stressed. Personally, I had very little experience in the OB and peds realm having no children or nieces or nephews myself. I felt like I had to study a lot more.
I liked third because they gave us a teensy bit more slack on the leash during medsurg clinicals. I could hang piggybacks with the nurse after getting checked off with my clinical instructor. We always had to be with the instructor when doing push meds. Gave us more practice giving report. Though the way they teach us is still nothing like they do in the real world!
I liked fourth semester the best! Good luck to you!