I feel like I'm a real failure

I'm sorry that you had to deal with that. Next time you go into the lecture hall, bear in mind that you're here to learn, the memory will come back into your head again but you'll need to take a deep breath and put it at the back of your mind. Work first, stress later.

Another thing you can do is to play the petty card: You can go and talk to your lecturer and ask her if she could help you improve the report or ask for her opinion of the report but in a 1 to 1 session. This easily brings up the topic to her and you can tell her that everyone in the class knew that it was your report and you worked hard on that report, so you felt hurt when she embarrassed you. This would make her realise that she shouldn't have diminished another student's work in front of many people. At this point you'll easily win here.

One more thing to mention is that you don't sound weak or stupid at all. Everyone can feel embarrassment but it's only human emotion. The fact that you are still able to go to your lectures just proves that you're a strong person. It's going to be hard to forget at first, but eventually that memory will mean nothing to you. Also remember that there are worse situations in life, for example, she could have mentioned your name in front of everyone or spoken to you directly about it in front of everyone, thankfully she didn't though. Try to look onto the brighter sides, because that way you'll focus on what didn't happen, and that way you won't remember what did happen.

Best of luck

You're right, I should've seen the good things here. I feel so angry and that's why the only thing in my mind is blaming myself and the situation. Thankyou so much this means a lot to me

Anytime! I hope things do get better ^.^