Spice Jet Airlines — rudeness

If you have other choice then never choose this spice jet.2 days ago i travelled with my mother (82years old on wheel chair) and my brother. We have total 50 kg check in luggage and 7 kg hand baggage. I request the check-in staff (Nawaz may be as i remember) allow this extra baggage and he is well informed that i am travelling with old age person but he behave me very rudely - he didnot even said in a good manner that i can 2 or 3 kg adjust - i request him it will be difficult for me to carry more hand baggage but that guy like a fool continued saying no no no?
Is this fare?
Check in and hand baggage go through different air craft or same?
In past i travelled with different air carriers
And except this spice jet all were helpfull but this experince was bitter
.2nd issue my mother has knee problem and at the time of booking confirmed with customer care for seats that these are more leg space and i paid extra but in flight these seats were normal seats compare to other seats. Today spice jet send me mail that they will return extra money. My mother were very uncomfortable on this seat due to not sufficient leg space
My question is now for this who is responsible