Yes girls can gain muscle but only about 60% as fast as guys. The best thing to do for gaining muscle is get a gym membership so u can have access to more weights. Or buy a bunch of weights for home. If you do manage to get gym access or more weights do the routine in the following article.(add www. to all links) ironechelon.webs.com/SuperStrength.htm
I guarantee you will gain muscle with this routine. Just make sure to follow all the instructions on the site that are included with the workout for best results. Stop doing some exercises now and then some more later. That's not optimal for muscle growth or for anything really.
Since those weights are all you have for now I'd say your best bet would be a bodyweight exercise routine. In other words a routine made of push ups, sit ups, etc that doesnt require weights. I would strongly suggest getting a pull up bar. Pull ups are awesome for your arms and back.
Here is a very good body weight exercise only routine:
teenbodybuilding.com/brent2.htm
It's called the Navy SEALS workout, and it consists of push ups, sit ups, pull ups, and dips. This workout focuses mostly on muscle endurance, but it will definitely help you gain some muscle, especially if you don't have much. If you can't do what's required for week one start with even less reps than that and work your way up until you can do it. Theres cardio parts to this workout as well, but you can just not do them if you want.
I would also suggest doing some military presses and bicep curls with your 10's and squats and lunges with no weight on your workout days right after the Navy Seals portion of the workout. Also don forget to eat lots of protein. One gram of protein per pound of body weight per day is a good amount fo muscle gaining.
Hope this helps and good luck
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