Problems with reading Quraan

Assalam o alaikum,Respected Mufti Sahab, I read 1 ruku of Quran daily. The problem is that I have not been to madarasah, so the pronounciation of the words of the quran does not come out correctly as how a qari or an alim of imam receites. But I have managed to correct some of the words. But still I cannot recite it with its exact makhraj and aslo some times get baffled that which words will come out from the throat, which will come out from the upper tounge. How will I pronounce small kaf and big kaf. How will I pronounce ze and zal as both seems to me same pronounciation then why the difference. How to differentiate between (to) and (te). So all these are bothering me. Also I do not have so much time to go to a qari or Imam to attend class and learn. Also I feel ashamed that I am over 30 yrs of age and if I go to study at madrasah where small children also study I will feel embarrased.
So sometimes I feel that I am making so many mistakes and cannot also pronounce correctly so it is better not to read Quran as there is high possibility of making mistakes and becoming a sinner. What a pity that being a muslim, born in a muslim family, regard my self a an Ummati of Beloved Rasul S.A.W (PUBH) and cannot read QURAN. What face I will show to my NABI. HOW SAD? What to do Mufti Sahab, I was taught reading quran at home by my mother and sisters and ofcourse there was english school and education which we put more stress upon and so this was the result. What to do now, suggestto me.