Re: Can't do side legs lifts and clamshells
I had the same trouble with straight leg lifts (lying flat on back). The PT suggested some easier exercises that would fire up the same muscles, the new exercises were much less painful, and the straight leg lifts were doable after about 2 weeks.
I also found the standing side leg lifts useful. Worked up to 2 sets of 15 before trying the lying side leg lifts.
As for the limp, try the standing marching exercise. Stand before a sink or table, hands on the table for balance, then left each knee straight up. My PT said that people who march regularly don't develop a limp.
I think that PT's put too much stock into what exercises you can do, and when you can do them. My PT got very upset when I couldn't do the straight leg raises. She emailed my OS, who got really worried himself and called me in for an exam. He was greatly relieved when he saw that I was really doing OK. It was all sort of silly, really. It makes more sense to measure progress by how you feel and what daily activities you can perform. And progress by that standard will come in its own good time.