Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Seek urgent medical help for severe or rapidly worsening symptoms, including chest pain, severe breathing difficulty, fainting, sudden weakness or speech difficulty, or a serious fall with a head injury.
These are not expected effects of occupational therapy and should not wait for a routine OT appointment.
The article also says
Contact your occupational therapist or healthcare team routinely if an activity programme causes increasing pain, repeated dizziness, unusual fatigue, or new difficulty completing daily tasks.
Also call if a splint or device causes redness, swelling, numbness, skin damage, or persistent pressure.
Report falls during therapy or at home, even if there was no obvious injury.
Your plan or equipment may need review.
Every sign above is quoted from the sofidex article on Occupational therapy. If you are not sure, err upward — it is always reasonable to be checked.