2 Months Post-Op Tummy Tuck and Now Having Stabbing Pain

Tags:2 months post-op

I had a tummy tuck 2 months ago and now I have bad pain near my belly button area. It bothers me most when I walk and it's a stabbing pain. Is this a sarcoma? 

Ever since my tummy tuck, my heart rate has risen dramatically. I've also had cellulitis and I'm currently taking strong antibiotics. I do feel confused at times and continue to have a rapid heart rate and pulse. Breathing is hard as well, and I have an especially physical job (courier). 

I'm off of work until Monday because of the infection I'm taking antibiotics for. Is what I have serious? I told my doctor about my concerns and he doesn't seem to be connecting the dots. He said he doesn't feel anything in my stomach, but I sure do and by the end of the night, my stomach from the belly button to the pubic area muscle is very tight and swollen. What should I do? I'm getting worried.