'91 Cav, 140000km, hesitates on acceleration up to 30km/hr

HELP!:crying:

My 1991 Chev Cavalier has 140,000km on it and it is starting to hesitate up on acceleration...but only between 15 and 40km/hr. After that it's fine.

I'm pretty broke and don't have access to public transit.

Is there any quick, simple, and/or cheap fixes I can attempt to do by myself or beg a guy friend to help me with?

Any suggestions would be greatly appreciated. If you need any further information I'll try my best to not sound like a silly girl

Oh, it's a 4 cyclinder and an automatic