Ouch
Everyone always picks on psych and PM&R... Fortunately I love my field and yes, we do have a bit of a self-image/confidence problem, in large part because so many people still don't know what we do (or that we exist...), or that there's an "&" in our abbreviation (I see too many notes saying "will consult PMnR.")
The joke I used to hear was if you spoke English and
had a pulse we'd take you, but that was referring to the field back in the 80's and 90's. Back in those days our field was filled with IMG/FMGs, people that failed to match ortho (PM&R was the back-up plan for many of them), and a few people genuinely interested in rehab. It was truly a non-competitive field. We just weren't well known.
I applied a few years ago when it was a bit less competitive, but it's a hard field to match into now just by virtue of the number of graduating US MD/DO's who want to go into the field and the lack of positions. Roughly 89-93% of US seniors applying to only PM&R get a spot (compared to 98% of US seniors applying to IM, 93-97% applying to EM, etc.). Fortunately (for applicants) our board scores remain low--I think we're the second to lowest scores, after psych, so it's easy to stick out of the crowd if you do well academically. In addition, that makes our field a little more forgiving of academic mistakes. The big key is applying to enough programs, which will be more important with red flags.
Psych seems to be getting slightly more popular, but like PM&R, scores are still generally low and genuine interest in the field and a personable affect really go a long way. Now is a good time to find mentors in the fields you're interested in--the easiest program to get into is typically your home program, and mentors can also guide you when it comes to clerkship performance and residency applications.
If the OP gets their act together and does not fail any future classes, passes Step 1 and 2 on the first try, they should be able to find a position (assuming they apply to enough programs) in any of the fields they mention--it's definitely doable. While most programs could probably care less about pre-clinical grades, multiple failed pre-clinical courses is still going to be a red flag. That's why it's so critical to not fail anything else going forward and avoid any future red flags. At least for PM&R and psych, strong clinical scores and strong USMLE scores (aim for above average) should more than make up for the failed pre-clinical courses.