I've noticed that in many teachings, books etc it is emphasised that something enters a sense door, sensation arises,then vedana then thought proliferates and I can understand this so far as a sound or smell etc but what I notice in my practice a lot is not that. What I notice is that thought arises followed by sensation for example a thought of a lost loved one followed by sadness or a sexual thought followed by particular physical sensations. Can someone please explain this. what ive read must only be talking about one aspect right? I don't feel a sexual sensation then think about it. Its the opposite.
When your thought arises, it is thought entering your mind's sense door. This is then followed by sensations and/or feelings arising. Because you can't see the subtleties why this thought of yours is arising, you think that it is not according to the teachings.
Putting too much attention on such subtle things as thoughts, sensations, feelings and what arises/comes first, etc. during meditation should be avoided, because most people's meditation skills are not high enough to see these subtle things and their order of appearance. Even if somebody has high meditation skills to see these subtleties, others who are not skilled in meditation could easily misinterpret such teachings and/or think that something is different in their minds, which is not.
External stimuli activate nerve sensors which transmit a signal to the brain - in the case of the 5 senses (taste, touch, smell, sight, and hearing). The other sensations you speak of are the result of bodily reactions to internal stimuli (called psychosomatic). These are reactions generally recognized by increased respiration or blood flow as the case my be. They are only semi-voluntary responses.
When one comes in touch with and object with the 6 doors one experiences sensation. When this object is identified it is received by the mind. This again cases sensations. This sensation can trigger further thoughts. When you crave for any of these sensations this case formations which can cause sensations both mental and physical. In this process, one might only part of the process if one is not very aware. Therefore, one might see sensations before or after in the alternating sequence.
Householder Arturia, interested,
"The eye (similar: ears, nose, tongue, body, intellect, it's objects and so on) is burning, forms are burning, eye-consciousness is burning, eye-contact is burning, also whatever is felt as pleasant or painful or neither-painful-nor-pleasant that arises with eye-contact for its indispensable condition, that too is burning. Burning with what? Burning with the fire of lust, with the fire of hate, with the fire of delusion. I say it is burning with birth, aging and death, with sorrows, with lamentations, with pains, with griefs, with despairs.
one having faith in the Tripple Gems, having faith that senses and theit objects as well as all phenomena around getting touched are not real, no refuge, not worthy to give into and hold on them, is called a faith follower, not able to die before not having seen for himself, one who agrees by intellect, a Dhamma-follower, likewise.
One who has seen for himself, that the the eye is inconstant, changeable, alterable. The ear... The nose... The tongue... The body... The mind is inconstant, changeable, alterable, and/or that feeling born of eye-contact is inconstant, changeable, alterable. Feeling born of ear-contact... Feeling born of nose-contact... Feeling born of tongue-contact... Feeling born of body-contact... Feeling born of intellect-contact is inconstant, changeable, alterable.... is called an stream-enter, a Noble One, no more able to fall from the path and gain low existances.
And how does one see for himself? By investigation it right on place - leading a good and virtuous renouncing life - with birth giving attention (yoniso manasikkara), here and now, all of the time taken for worthy giving into: Satipatthana Sutta: Frames of Reference
(note that this Gift of Dhamma is not given for trade, stacks, exchange or entertainment, but for ones work trough maccharia to escape the wheel here and liberation)