Is she interesed if in her text are a lot of hehe and haha? :P

I have been texting this certain girl but real cool calm bout it, when she replies there is usually more then what she has to say, and a lot of hehe and haha ;P etc, does this mean she is interested , the text are some what sometimes long but doesn't really ask me questions , but I don't ask a lot either because I don't want to come on to strong , is she maybe doing the same, at the start she was texting back kinda quick , quicker then me anyway, and now towards the last few text the last 3 or 4 she hasn't text back for like 2 and 3 hours and the last text she wrote to me it took her 2 and half hours and when I got it that night I just left it till the next day round lunch time then replied but I didn't get one back , maybe playing reserved and doesn't want to look to keen like me , or do you think she just texts me just to be nice
Is she interesed if in her text are a lot of hehe and haha? :P
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