I was born a christian and as a Christian/Catholic I made a vow of celibacy to Jesus.I am now hindu.must I follow this vow?would I go to hell for breaking this vow?
You won't go to hell for breaking your vow, but yes there would be karmic consequences (as also mentioned in one of the comments) and you might not get liberation:
pādās trayo bahiś cāsann
aprajānāṁ ya āśramāḥ
antas tri-lokyās tv aparo
The spiritual world, which consists of three fourths of the Lord’s energy, is situated beyond this material world, and it is especially meant for those who will never be reborn. Others, who are attached to family life and who do not strictly follow celibacy vows, must live within the three material worlds.
So as the above verse from Śrīmad-Bhāgavatam 2.6.20 states those who break vows especially the vow of celibacy remain in the material world.
Changing religions or faiths doesn't change the rules of a particular vow.
The reason you are asking seems that you have already broken vow, in that case beg for forgiveness from Jesus and also from the hindu deity you are trying to worship. Sincere apologies never go in vain. Even the Mahajan - Yamaraja begs for forgiveness (Śrīmad-Bhāgavatam 6.6.30), so we should follow - mahAjano yena gatAh sa panthAH:
tat kṣamyatāṁ sa bhagavān puruṣaḥ purāṇo
nārāyaṇaḥ sva-puruṣair yad asat kṛtaṁ naḥ
svānām aho na viduṣāṁ racitāñjalīnāṁ
kṣāntir garīyasi namaḥ puruṣāya bhūmne
O my Lord, my servants have surely committed a great offense by arresting a Vaiṣṇava such as Ajāmila. O Nārāyaṇa, O supreme and oldest person, please forgive us. Because of our ignorance, we failed to recognize Ajāmila as a servant of Your Lordship, and thus we have certainly committed a great offense. Therefore with folded hands we beg Your pardon. My Lord, since You are supremely merciful and are always full of good qualities, please pardon us. We offer our respectful obeisances unto You.