Hope your pain has got better. If still not, visit a good physiotherapist and let them assess the problem. Pain after lifting heavy weight can be due to muscular spasm or facet joint locking. You can get the treatment of both via physiotherapy. Modality treatment with ice pack or hot packs (depending upon the type of injury)will help u recover faster.

Rest must physiotherapy treatment and avoid exercise at this time

• Bhujang Asana – Lie flat on your stomach, keeping the palms out, bend the neck backward, take a deep breath and while holding it for 6 seconds, raise the chest up. Release breath and relax your body. Repeat the exercise 15 times twice daily.

Rest on hard surface if radiating then flex your knee to 60-90degree in supine position. Avoid forward bending ,stair climbing,lifting heavy objects.start physiotherapy session with ultrasonic and diathermy. Sometimes cryotherapy. Refer nsaids together for Better  result.

Hi, Greetings S/W engineer, Hope you too much weight. Try to reduce your muscle make fit yourself. Please follow the below things 1. Pend forward slowly and steadily how much you can repeat the same 3 times. 2. Apply hot water fomentation

Hi sir put ice pack and start physiotherapy

Try these stretches: https://apmhealth.com/educational-resources/healthy-living-tips-and-resources/2-uncategorised/185-6-stretches-to-help-back-pain-ebook If you still don’t feel any relief then meet a physiotherapist.