Why My Heart Feels So Weighed Down During Prayer

Assalamu alaikum, I'm a 17-year-old Muslim and I've always had a bit of an up-and-down journey with my salah. Lately, I've been putting in a real effort to pray all five salah on time, alhamdulillah. But here’s the thing: every single time I stand for prayer, my chest just gets so heavy. I start to feel like I'm on the verge of a panic attack-my breathing gets short and actually hurts a little. I can’t tell if it’s guilt from all the prayers I’ve missed before and past mistakes, and I worry that Allah SWT won’t forgive me no matter how much I repent. Sometimes I wonder if it’s shaytan trying to mess with me too. This feeling has been really getting to me, to the point where I almost dread salah and just want to rush through it so the heaviness goes away. Has anyone else ever felt like this?