Yep, Clara, it is absolutely normal! I waited five weeks to go to Curves, which is mainly aerobic (the weights aren't heavy) but it was eight weeks until I returned to the YMCA for weight training.
After three sessions, I had this hard lump on my right hand side which was painful and felt like it was protruding, kyethra, and I was positive I had a hernia!
Nope, when the surgeon checked it out he said "Silly! That's your port!"
Needless to say, I've changed up my routine to eliminate the exercises that were killing my port (leg press) and reduced the weight on those that just agitate it (leg curls, leg extensions, bench press).
My port is on the right hand side, though and is just off my port incision--don't know if that's worse than being on the left--probably they're both the same!!