Leaves appear crinckled

Unless you are growing a pepper variety with distinctive foliage, it's impossible to know what you have until it starts forming pods.

As for the leaves, it's a classic sign of stress in the plant. It's not the end of the world, as long the plant is still growing the symptom usually goes away after a while. Could be stress from bugs (aphids or spider mites), temperature fluctuations (peppers like their soil pretty warm, which doesn't happen early in the season), light fluctuations, nutrient fluctuations, water fluctuations, etc.

I would check carefully on the underside of the leaves and the soil surface for signs of bugs (visible eggs or insects, white sticky residue, spider-web like filaments). Aphids especially like new growth. If you don't find anything, try to be as consistent as possible in your watering and fertilizing, keeping in mind that peppers like their soil on the dry side and do not like high amounts of fertilizer.

If you are growing in a pot, your soil may be a bit on the dense side for containers as garden soil tends to compact in pots; most people here use potting mix or potting soil to avoid that problem. It might be worth it to repot the plant in a mix more suitable for containers, otherwise be especially careful not to overwater as you can rot out the roots. If you are growing in the ground, obviously ignore this paragraph. But I would still check that you are getting good drainage.

I haven't fertilized my plants yet. The soil is pretty dry. I checked for bugs as you suggested. The plant did not have any - so ruled that one out.

I am from the southern tip of India, we basically have one season year long - summer. right now, I am getting 85F min and 104F max and it will stay this way (more or less) till September. Kinda sure its not the cold.

The soil does appear dense to me.. Will take you advice and try replanting in a potting mix. I don't have enough space to plant them. So I am growing two side by side. Can that be the reason?

This malaise has been discussed many times at multiple forums with many different opinions on the malady as noted above, try these, distorted naga leaves, Wrinkles Leaves Diagnosis Assistance, Bumpy Pepper Leaves and Plant Problems. The general consensus is it mostly happens to C. chinense and there seems to be no rhyme or reason as to which plants it seems to afflict, you can have two plants from the same seed batch grown in the same media & given the same ferts yet one has these symptoms but the other doesn't. If you don't have any bad bugs I'd like to add this treatise to the above list, Ordering Seedlings Online, and as you will read there are many ways the problem was resolved from flushing the growing media to changing fert levels and using Smokemaster's Witches Brew which I had success with.

If I was to offer the #1 piece of advice given over the many posts about this problem it would be, if the plant has no other growth issues and it's producing fruit it's not a problem in itself. If, however, the plant has yellowing leaves, stunted growth and/or poor fruit production, try any of the methods that were reported to help the issue.

Yeah, cold is definitely not your problem. I'd say with your climate and growing in containers you will definitely need to watch the plants and make sure they don't dry out during the worst heat of the day. Pepper plants can droop a little during the hottest hours and then when things cool off they will pop back up. If you notice they are not then you need to find out why and correct it. More water, or even rigging up some light shade may be in order. A layer of mulch over the soil surface will help keep the soil temp from heating up too much. Also, yes, putting two plants in one container forces them to compete for water and nutrients and can stress them more. Container gardening is very different than in ground; there is a forum here that discusses the tricky aspects of it. Basically they will need water and fertilizer more often. I generally feed my plants when the blossoms start to open.

Heat stress can also cause it. Water in the mornings if the leaves still look wilted. In the heat you are having they will look wilted by the end of the day. With the heat you are having avoid using fertilizers until night time lows are under 75 and day time highs are below 95. This is to avoid burning the roots.

The leaves appear to have straightened out and the plants are blooming. Guess improving drainage worked. However, the plant that I have in the sun is dropping flowers as soon as they bloom. The ones in the shade are doing better. I guess this is related to heat. waiting for the temperature to go down.

Don't worry about dropping blooms. The plants will hold them when the time is right. There are dozens of reasons for it and usually temps are the main one. But eventually, they will set and produce pods.