Wanting it and not wanting it.

Assalamu Alaikum wrwb, I had a few questions regarding marriage and I have been very unclear and I need proper guidance on this. Around last year, I got engaged and it broke off due to some issues. However, when I get proposals, is it important for me to tell them this (whoever proposes)? Another question I had regarding marriage is that when I get proposals, I tend to automatically think to myself that I am going to say no, not for any particular reason, but simply just because I am not interseted, but I do istikhaara anyway, because although I am young, I am at a marriageable age and I don't want to lose my chances with a proposal and my parents play a big part because they often tell me or ask me what reason I have to say no which puts me in a lot of pressure. How do I know I am ready and how do I know it's good for me? I have heard of many sheikhs and ulama saying the signs of when you are ready for marriage and I feel like I don't meet some of them. Are my emotions playing a big role in this and am I being unreasonable with unnecessary doubts, or are my thoughts valid? Jazakallahu Khayran