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 emergency care for a sudden, extremely severe headache accompanied by vision loss, double vision, vomiting, fainting or confusion.
Rarely, this pattern can occur when there is sudden bleeding into a pituitary tumour.
If you have diagnosed adrenal insufficiency, follow your emergency plan and seek urgent help for severe weakness, repeated vomiting, collapse or confusion.
These symptoms relate to cortisol deficiency rather than hypogonadotropic hypogonadism itself.
Contact your healthcare team promptly if you have new headaches, changes in peripheral vision, unexplained breast milk production, excessive thirst or frequent urination.
These may indicate a pituitary problem that needs assessment.
Arrange a routine medical appointment if puberty has not started within the expected age range, puberty begins and then stops progressing, or menstrual periods are absent or have stopped without a known explanation.
The article also says
You should also seek assessment for persistent low sexual interest, erection difficulties, infertility, hot flushes at an unusually young age or symptoms of low sex hormones after pituitary surgery, head injury or brain radiation.
Every sign above is quoted from the sofidex article on Hypogonadotropic hypogonadism. If you are not sure, err upward — it is always reasonable to be checked.