You say “I’ve been trying to follow the BBM pain & rehab protocal of trying to find an entry point and building back up”, but we probably need to dig into that a bit more.
As discussed here (recommended reading):
if the individual experiences persistent or worsening symptoms during/after training with this approach, a temporary change in the exercise altogether may be needed. There are no “right” or “wrong” exercises in this situation, but rather exercises that should target the affected area in a way that is tolerable to the individual. This may involve minor changes, such as swapping low bar squats for front squats, or more significant changes may be required. This may even involve unilateral work like substituting barbell squats for weighted lunges, or deadlifts for single-leg RDLs.
In practice we often combine these approaches, including both a VARIETY of bilateral and unilateral exercises directed at the affected area, given that many individuals exhibit movement compensation to off-load symptomatic areas (e.g., shifting away from a painful side in the squat). This step can sometimes present challenges for individuals who have strong psychological attachments to particular exercises, but we would prefer to build physical and psychological resilience to tolerate a wide variety of movements and movement styles without fear or perception of threat.
If you are bench pressing, I agree with your use of tempo, but the rep range should probably be no fewer than 10-12 reps per set, and staying relatively far from failure (i.e., nothing at or above 8 RPE). I would also experiment with other forms of benching & pressing (incline, dumbbell, unilateral machine).
The same would apply for overhead work; you say any of them are painful with minimal load, but perhaps you can tolerate a high incline with a very light dumbbell as a starting point.
I would also be performing horizontal and vertical pulling (e.g., cable rows/lat pulldowns, dumbbell rows, etc.).
And if you are still experiencing increasing pain after your sessions, re-evaluate the intensity of loading as the initial variable:
Once this entry point is found, our goal is to begin stringing together a series of small victories in order to build positive physical and psychological momentum. In this way, the nature of progression becomes critically important, as overly aggressive jumps in loading dosage increase the risk of symptom exacerbations.
A key point here is that being “pain free” is not typically a realistic short-term goal; symptoms are always a part of the rehabilitation process, and there will be ups and downs along the way. An increase or recurrence in symptoms may be related to a number of factors, including the dosage of stimulus (external intensity, volume, etc.), but also due to outside biopsychosocial factors such as anxiety, sleep disruption/restriction, life stressors, concurrent medical illness. This is an opportunity to reiterate that “hurt does not equal harm,” that symptoms are an expected part of the process, and that we have strategies to mitigate symptoms — typically by modifying the dosage and type of loading.
We suggest that initial loading increments be conservative. If symptoms remain constant (i.e., neither exacerbated nor improved), we may even keep the absolute load constant for a few of the initial sessions to begin observing a de-sensitization effect. Once we observe this effect, we can begin incrementing loads across non-consecutive sessions. There is no “optimal” increment to use in terms of absolute weight (e.g., 2.5-5 lbs at a time), or relative increases (e.g., 5-10% of load) from session to session, but we may give individuals who are looking for specific guidance these sorts of arbitrary suggestions. However, we qualify this advice since we do not want to imply that the process will be linear. Neither strength acquisition nor injury rehabilitation are straight-line, predictable affairs. Rather, we should maintain flexibility in our approach to allow for the “up” days where we may be able to increment a bit more, as well as the “down” days where we may need to adjust loading down or hold it constant depending on the nature of symptoms during and between sessions.
The most common errors made in this process involve overly aggressive increments of loading despite worsening symptoms, which often results in the process taking longer than necessary.