Don't get me wrong, the date is lovely and her blushing is CUTE, but she's become this suddenly complicated girl and the whole date thing is just......too tropey to belong to her at this current time point (hell, this is the "most date" date so far imo and it's with her out of all people?). Like I don't even think she is capable of recognizing that titjob takoyaki being inappropriate, let alone dropping them on the floor wasting food on purpose? Is this the same ramen girl we know?
Here's the thing. Tsuneyo is masking.
She is coded as being on the autism spectrum -- she's very literal, she doesn't pick up on sarcasm, she has a well-defined special interest (noodles), misses subtext regularly, and we've seen that she's been masking in the past (we briefly see the real Tsuneyo at the end of the second Halloween event when she walks in on Akira and Molly).
Her father probably sheltered her to protect her, because public schools can be a harsh place for someone on the spectrum, so she's not as world wise as the other girls, but she's also probably not as naive as she plays. She came to an awfully quick assumption about what happened at Halloween for someone who projects the level of naivette she does.
So when Sensei spends the day with her, she reflects on the media she's consumed with Molly, and acts like a girl in a romance anime. She doesn't know how to act, so she's faking it. It's what she always does. We won't see the real Tsuneyo with any regularity until she feels safe to drop her mask or until she's forced to -- either because she's too exhausted to keep it up, or she's in emergency mode like she was in that Halloween event (or when Yumi was attempting to kill Nodoka, I think that was a mask-off moment as well)