Baffled by assessment

I had my assessment yesterday and im really struggling to understand it. I went in totally blind without reading any info about how the assessment may be. 

They already had a 2 hr conversation with my mother over the phone abiut a year before my assessment. I had loads of questionnaires to fill out to take to my actual assessment too. 

When i went in there it lasted 30 mins. She told me before we started that i would have this assessment today and have another app in 6 weeks. I asked her what the other app was and she said it was a app for the diagnosis. 

I think my assessment went bad. She talked alot about useless stuff, asked me to discribe emotions, asked about bullying, friends, colleagues. She gave me 4 tasks. A task with a pattern i had to make and then asked what it looked like. A task showing her how to brush my teeth, a picture book task and i got given 5 objects to create a story with. She also gave me like a oldstyle radio and toys to play with whilst she caught up on her notes which i didnt touch.

I couldnt do the last task and she seemed to get very ticked off by it. I have no imagination anyway but when im nervous my mind goes totally blank and i just couldnt come up with some story about 5 unrelated random objects. 

Im wondering if what im describing is normal? I went in hoping they would ask more about my experiences and my childhood and why i do certain things. I came out feeling like id been treated like a child and wasted 30 mins of my time. I feel deflated that i waited four years for a 30 min talk and im unsure how i can be diagnosed when theyve only spoke to me for 30 mins.