I was using a jvc gr-sxm515 using a sony VHSC tape when I did a play back it was like fast forward with lines across it never did this before nieces wedding
Something in the camera is damaged, likely a severe alignment issue. What you're seeing could be one of several things.
One problem I've seen is the tape may not know what speed it was recorded in, due to damaged recording from a damaged camera. If you can play it back in a VCR where speed is set rather than auto-detected, it may help to isolate the issue. Unfortunately, only the oldest 1980s VCRs tend to have manual playback speed settings.
For something like this, I'd have to see the tape, run it through some equipment here, and see how it reacts.