Giach is a verb. Gachon is a noun.
גחן to curve, bend, bow, stoop.
— Qal - גָּחַן he bent, stooped.
— Hiph. - הִגְחִין he bent, stooped. [Aram. גְּחֵן, Syr. גְּהֵן, Egypt.–Aram. and Mand. גהן (= he bent, bowed, stooped). According to Barth related to Arab. janaḥa (= he inclined, leant. גחן is prob. the base of גָּחוֹן. cp. גהר.] Derivatives: גָּחוּן, גְּחִינָה.
גָּחוֹן m.n. 1 belly (of reptiles). NH 2 venter (anatomy, zoology). [Prob. derived from גחן.] Derivative: גְּחוֹנִי.
חה ᴵג to draw forth (a hapax legomenon in the Bible, occurring Ps. 22:10 in the suff. part. גֹּחִי). [Prob. related to גיח.]
גיח to burst forth.
— Qal - גָּח it burst forth.
— Hiph. - הֵגִיחַ he caused to burst forth. [BAram. מְגִיחָן (= they burst forth), JAram.–Syr. גָּח, Arab. jāḥa (= it burst forth). cp. גחה ᴵ and נגח.] Derivatives: גִּיחָה, הֲגָחָה. cp. גחה ᴵ.
you keep mixing up words. The verb root g-ch means to burst forth. The way it is used in Genesis is as a noun referring to the belly (not the womb). In every case, when the verb form is used, the verb is connected to a noun. In this case, the noun (your belly, gachoncha) is attached to a verb (telech, you will go).