Does she want sex from me or attracted to me or is she just being nice to me?

this woman shes 50 years old and im like 20 but she stares at me,like i'll see her looking at me and she would still be looking then i look back at her and she'll look down at her paper or look to the side.or sometimes when shes talking to someone she'll look directly at me.one day her sister had got sick and she told some people what happened to her and she said it in a sad tone but when she came and to ld me what happened she seemed all happy ad stuff,now that i dont understand.when she came to sit by me, she pushed me over with body to sit down and our thighs were touching she didn't bother to move them at all then she put her hand on my thigh to say something then i moved a few inches away i didnt want her to uncomfortable by me.. and she seemed nervous because she was shaking her leg and taking her glasses on & off.then i felt her breath like she was breathing hard and i heard it a little.she never did that before idk what to think.and she offers to buy me things to and take me and my two younger siblings out .im the only one she actually bought things for.she did mirror me maybe 2 or 3 times.tell me ur opinion