What aroused Yakov's ire against Lavan?
Ramban and Seforno: Initially, Yakov was concerned lest one of his wives or slaves had stolen the Terafim. But when Lavan found nothing, he concluded that Lavan's claim was merely a pretext to search Yakov's belongings - because Lavan suspected him of stealing something of his. 1
Oznayim la'Torah (citing Seifer ha'Carmel in the name of the Malbim): The Torah writes "Vayichar le'Yakov" and not "Vayichar Apo", because it was not not with Lavan with whom Yakov was angry, but with himself - in that he must have sinned for this to be happening to him. 2
Indeed, following Lavan's dishonest treatment, (refer to 31:39:1:1) Yakov had every right to take whatever he could as compensation, as he goes on to tell Lavan in no uncertain terms.
Oznayim la'Torah: The Midrash Rabah makes the same observation, based on Yakov's own words "Mah Pish'i u'Mah Chatasi?"
What does "Ki Dalakta Acharai" mean?
Tosfos ha'Shalem (35:2): It is like one who pursues, and his heart is burning (Dolek).
Tosfos ha'Shalem (4, citing R. Efrayim): You burned (pursued rapidly like fire) after me.
Why does it say "va'Ya'an Yakov"? (The Torah usually says "va'Yomer" even when one responds.)
Tosfos ha'Shalem (2): Amidst anger, Yakov raised his voice. "Oneh" connotes loudly - "v'Anu ha'Leviyim ...Kol Ram."