Maha Saccaka SuttaMaha Saccaka Sutta your body should not be stained. So if your are fatigues maybe try lying posture. Also if you muscles are tensed loosen them. Sometimes you facial muscles may become tense. Best way to loosen them is to smile. Also smiling reduces tension and brings about pleasant or neutral sensations.
Conceptualisation happens in verbal fabrication. Verbal fabrications is not explicitly mentioned in the Anapana Sutta but should be calmed before calming the mental fabrication. This can be achived by keeping your attention focused on a object you are bringing down creation of new verbal fabrications. In the Abhidhamma there is 5 fold Jhana classification. In the Sutta there a 4 fold classification. In the Suttas the 1st and 2nd Jhana in the Abhidhamma system is amalgamated into one. The 1st Jhana has initial application and the 2nd Jhana is sustained application in the Abhidhamma system and in the Sutta system both initial and sustained application is considered in the 1st Jhana. Initial and sustained application is what enables thinking and conceptualisation. Once these fall away (Abhidhamma 3rd Jhana and Sutta 2nd Jhana) there is no conceptualisation or the mind does not have the ability to think or conceptualise. The definition of verbal fabrication is found in Cūla Vedalla SuttaCūla Vedalla Sutta and Aṭṭhaka,nāgaraAṭṭhaka,nāgara Sutta mention how verbal fabrication is stilled after the 1st Jhana.
What is proper meditation is if the meditation helps reduce your mental defilements. If your pratice feeds into it you are doing it wrong. See Pahāna SuttaPahāna Sutta which is a short description of letting go of the roots and Avijja Pahana Sutta 2Avijja Pahana Sutta 2 which concentrated on ignorance.
Also see: Ānâpāna,sati SuttaĀnâpāna,sati Sutta
