before you fall asleep or right after you /when trying to wake up??? it's probably hypnagogic hallucinations - i have the kind upon waking called hymopotic or something although very very similar / also have sleep paralysis with this!! Mine dreams usually terrify me;(
Hi, welcome to the forum, you are going through visual hallucinations which seen due to neuroophthalmologic dysfunction resulting from a wide variety of underlying etiologies. This condition can overlap with visual illusions which include distortions of size (micropsia or macropsia), shape (metamorphopsia), and color (dyschromatopsia).
The type of hallucinations you are experiencing is known as Complex or formed hallucinations as you see things with details like animals, people etc (flowers and spider in your case). In such cases it is very important to note any other conditions like eye problems, stress, confusion, memory loss, alcohol, drug, and medication history is also important.
Conditions which can present with such symptoms are Migraine (aura manifests as visual hallucination), Seizures, Alcohol and drug use, psychiatric illness and metabolic encephalopathy.
You need to undergo polysomnyography (PSG) to rule out sleep disorder, EEG to rule out any epileptic foci, and also psychiatric evaluation which will help to rule out any factor.
I suggest you to sleep with lights on, good sleep hygiene, long acting sedatives against prescription will help you maintain sleep, keep away from any triggering factor (smell, food etc. need to be identified.), share your inner feelings with family and friends, hot and cold water bath will help you to alleviate condition.
I suggest you to consult neurophysician/psychiatrist for further evaluation. Take care and regards.