stops crying when picked up...

[ablack]

My daughter will play on the floor or in her walker for a short while, (sometimes 30 minutes, other times 10 minutes) and will then become fussy.  If I pick her up, she is fine.  But I find that is it hard to accomplish daily tasks while holding a 20 lb. baby.  I also do not want to be teaching her that crying means she gets picked up.  I sometimes try to talk with her without picking her up, but she will keep fussing most of the time.  I will often sit in the floor behind her while she sits up and plays and she really likes that.   
Is it expecting too much for her to be up for around 2 hours and not be fussy?  Maybe I should be more proactive in creating activities for her to do?  Any ideas/ suggestions?

[ablack]

oops!  i forgot to include that...she is 7.5 months old. 

as I posted yesterday, I felt like I already knew but just wanted to get another opinion.  I have been adjusting her to 2 naps rather than 2 and a catnap in the afternoons.  And she is doing much better all the way around (at least she did yesterday and this morning).  She has been less fussy in between but I have also been trying to introduce new activities to her as well.  I feel like I get into a routine and then just kinda stay there and she is ready to learn and move on to new things.

Any suggetions or thoughts would be appreciated.